US20070244483A9 - Inter-cervical facet implant with implantation tool - Google Patents

Inter-cervical facet implant with implantation tool Download PDF

Info

Publication number
US20070244483A9
US20070244483A9 US11/429,733 US42973306A US2007244483A9 US 20070244483 A9 US20070244483 A9 US 20070244483A9 US 42973306 A US42973306 A US 42973306A US 2007244483 A9 US2007244483 A9 US 2007244483A9
Authority
US
United States
Prior art keywords
implant
facet
facet joint
spacer
inter
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
US11/429,733
Other versions
US8029540B2 (en
US20070016195A1 (en
Inventor
Charles Winslow
Steven Mitchell
John Markwart
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Medtronic PLC
Original Assignee
Saint Francis Medical Technologies Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to US11/429,733 priority Critical patent/US8029540B2/en
Application filed by Saint Francis Medical Technologies Inc filed Critical Saint Francis Medical Technologies Inc
Priority to US11/447,413 priority patent/US8118838B2/en
Assigned to ST. FRANCIS MEDICAL TECHNOLOGIES, INC. reassignment ST. FRANCIS MEDICAL TECHNOLOGIES, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MITCHELL, STEVEN T., MARKWART, JOHN A., WINSLOW, CHARLES J.
Publication of US20070016195A1 publication Critical patent/US20070016195A1/en
Assigned to BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT reassignment BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT SECURITY AGREEMENT Assignors: ST. FRANCIS MEDICAL TECHNOLOGIES, INC.
Publication of US20070244483A9 publication Critical patent/US20070244483A9/en
Assigned to KYPHON INC. reassignment KYPHON INC. MERGER (SEE DOCUMENT FOR DETAILS). Assignors: ST. FRANCIS MEDICAL TECHNOLOGIES, INC.
Assigned to KYPHON, INC. reassignment KYPHON, INC. TERMINATION/RELEASE OF SECURITY INTEREST Assignors: BANK OF AMERICA, N.A.
Assigned to MEDTRONIC SPINE LLC reassignment MEDTRONIC SPINE LLC CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: KYPHON INC
Assigned to KYPHON SARL reassignment KYPHON SARL ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MEDTRONIC SPINE LLC
Priority to US13/197,841 priority patent/US8425530B2/en
Publication of US8029540B2 publication Critical patent/US8029540B2/en
Application granted granted Critical
Active legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/02Surgical instruments, devices or methods, e.g. tourniquets for holding wounds open; Tractors
    • A61B17/025Joint distractors
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/56Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor
    • A61B17/58Surgical instruments or methods for treatment of bones or joints; Devices specially adapted therefor for osteosynthesis, e.g. bone plates, screws, setting implements or the like
    • A61B17/68Internal fixation devices, including fasteners and spinal fixators, even if a part thereof projects from the skin
    • A61B17/70Spinal positioners or stabilisers ; Bone stabilisers comprising fluid filler in an implant
    • A61B17/7062Devices acting on, attached to, or simulating the effect of, vertebral processes, vertebral facets or ribs ; Tools for such devices
    • A61B17/7064Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02Prostheses implantable into the body
    • A61F2/30Joints
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/02Surgical instruments, devices or methods, e.g. tourniquets for holding wounds open; Tractors
    • A61B17/025Joint distractors
    • A61B2017/0256Joint distractors for the spine

Definitions

  • This invention relates to interspinous process implants.
  • the spinal column is a bio-mechanical structure composed primarily of ligaments, muscles, vertebrae and intervertebral disks.
  • the bio-mechanical functions of the spine include: (1) support of the body, which involves the transfer of the weight and the bending movements of the head, trunk and arms to the pelvis and legs, (2) complex physiological motion between these parts, and (3) protection of the spinal cord and the nerve roots.
  • spinal stenosis including, but not limited to, central canal and lateral stenosis
  • facet arthropathy spinal stenosis
  • Spinal stenosis results in a reduction foraminal area (i.e., the available space for the passage of nerves and blood vessels) which compresses the cervical nerve roots and causes radicular pain.
  • cervical radiculopathy secondary to disc herniation and cervical spondylotic foraminal stenosis typically affects patients in their fourth and fifth decade, and has an annual incidence rate of 83.2 per 100,000 people (based on 1994 information).
  • Cervical radiculopathy is typically treated surgically with either an anterior cervical discectomy and fusion (“ACDF”) or posterior laminoforaminotomy (“PLD”), with or without facetectomy.
  • ACDF anterior cervical discectomy and fusion
  • PLD posterior laminoforaminotomy
  • the present invention addresses this need with implants and methods for implanting an apparatus into at least one facet joint of the cervical spine to distract the cervical spine while preferably preserving mobility and normal lordotic curvature.
  • FIG. 1 shows a lateral view of two adjacent cervical vertebrae and spinous processes, highlighting the cervical facet joint.
  • FIG. 2 depicts a lateral view of the cervical spine with spinal stenosis.
  • FIG. 3A depicts correction of cervical stenosis or other ailment with a wedge-shaped embodiment of the implant of the invention positioned in the cervical facet joint.
  • FIG. 3B depicts correction of cervical kyphosis or loss of lordosis with a wedge-shaped embodiment of the invention with the wedge positioned in the opposite direction as that depicted in FIG. 3A .
  • FIG. 4 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention including a screw fixation device for attaching to a single vertebra.
  • FIG. 5 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising screw fixation of two implants, one implant fixed to each of two adjacent vertebrae.
  • FIG. 6 shows cervical spine kyphosis, or loss of lordosis.
  • FIG. 7 shows correction of cervical kyphosis, or loss of lordosis, with a further embodiment of the implant of the invention comprising two facet implants with screw fixation.
  • FIG. 8 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet implant and a keel.
  • FIG. 9 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising facet implant, a keel, and screw fixation.
  • FIG. 10 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet implant with teeth.
  • FIG. 11 depicts correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet implant with teeth and screw fixation.
  • FIG. 12 depicts correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants having bony in growth surfaces.
  • FIG. 13 depicts correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants having bony in growth surfaces and posterior alignment guide.
  • FIG. 14 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants with increased facet joint contact surfaces.
  • FIG. 15 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants having bony in growth surfaces and screw fixation.
  • FIG. 16 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants with articular inner surfaces.
  • FIG. 17 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet joint implant with a roller.
  • FIG. 18 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet joint implant with a plurality of rollers.
  • FIG. 19 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet joint implants, screw fixation, and elastic restraint.
  • FIG. 20 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet joint implants, screw fixation, and spring restraint.
  • FIG. 21 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet joint implants, screw fixation, and magnetic restraint.
  • FIG. 22A shows a perspective view of a further embodiment of implant of the invention.
  • FIG. 22B shows a perspective exploded view of the embodiment of the invention shown in FIG. 22A .
  • FIG. 23A depicts a posterior view of the embodiment of the implant of the invention shown in FIG. 22A .
  • FIG. 23B shows a posterior view of a locking plate of the embodiment of the implant of the invention shown in FIG. 22A .
  • FIG. 24A depicts a lateral side view of the embodiment of the implant of the invention shown in FIG. 22A .
  • FIG. 24B shows a lateral side view of the keel of the locking plate of the embodiment of the implant of the invention shown in FIG. 22A .
  • FIG. 25A shows a perspective view of a further embodiment of the implant of the invention.
  • FIG. 25B shows a side view of the embodiment of the implant of the invention in FIG. 25A , having a curved, uniformly-thick artificial facet joint spacer or inter-facet spacer including a tapered end
  • FIG. 26A shows a perspective view of a further embodiment of the implant of the invention.
  • FIG. 26B shows a posterior perspective view of the embodiment of the implant of the invention depicted in FIG. 26A .
  • FIG. 27A depicts a side view of the embodiment of the implant of the invention shown in FIGS. 26A and 26B .
  • FIG. 27B shows a posterior view of the embodiment of the implant of the invention shown in FIGS. 26A, 26B , and 27 A, implanted in the cervical spine.
  • FIG. 28A depicts a posterior perspective view of a further embodiment of the implant of the invention.
  • FIG. 28B depicts a side view of the embodiment of the implant of the invention shown in FIG. 28A .
  • FIG. 29A depicts a side view of an embodiment of a sizing tool of the invention.
  • FIG. 29B depicts a top view of an embodiment of the sizing tool of the invention depicted in FIG. 29A .
  • FIG. 29C depicts a perspective view of an embodiment of the sizing tool of the invention depicted in FIGS. 29 A-B.
  • FIG. 29D depicts a side view of the head of the sizing tool of the invention depicted in FIG. 29A
  • FIG. 29E depicts a cross-sectional view of the head of the sizing tool of the invention depicted in FIGS. 29 A-C.
  • FIG. 30 is a flow diagram of an embodiment of a method of the invention.
  • FIG. 31A is posterior view of a further embodiment of the implant of the invention.
  • FIG. 31B is a side view of an embodiment of a locking screw of the implant of the invention depicted in FIG. 31A .
  • FIG. 32 is a posterior view of a further embodiment of the implant of the invention.
  • FIGS. 33A and 33B depict initial and final insertion positions of the embodiment of the invention depicted in FIG. 32 .
  • FIG. 34A is a posterior view of a further embodiment of the implant of the invention.
  • FIG. 34B is a side view of a further embodiment of the implant of the invention.
  • FIG. 35A is a perspective view of an embodiment of the implantation tool of the invention.
  • FIG. 35B is a perspective view of the engagement head of the implantation tool of the invention.
  • Embodiments of the present invention provide for a minimally invasive surgical implantation method and apparatus for cervical spine implants that preserves the physiology of the spine.
  • embodiments provide for distracting the cervical spine to increase the foraminal dimension in extension and neutral positions.
  • Such implants when implanted in the cervical facet joints, distract, or increase the space between, the vertebrae to increase the foraminal area or dimension, and reduce pressure on the nerves and blood vessels of the cervical spine.
  • the facet joints in the spine are formed between two vertebrae as follows.
  • Each vertebra has four posterior articulating surfaces: two superior facets and two inferior facets, with a superior facet from a lower vertebra and an inferior facet of an upper vertebra forming a facet joint on each lateral side of the spine.
  • the upward inclination of the superior articular surfaces of the facet joints allows for considerable flexion and extension, as well as for lateral mobility.
  • Each facet joint is covered by a dense, elastic articular capsule, which is attached just beyond the margins of the articular facets. The capsule is larger and looser in the cervical spine than in the thoracic and lumbar spine.
  • the inside of the capsule is lined by a synovial membrane which secretes synovial fluid for lubricating the facet joint.
  • the exterior of the joint capsule is surrounded by a capsular ligament. It is this ligament and the joint capsule that must be cut in the embodiments of the method described herein for inserting the artificial facet joint.
  • an implanted interfacet spacer of 1.5 mm to 2.5 mm in width can result in interfacet distraction that increases foraminal dimension in extension and neutral.
  • Other interfacet spacer dimensions also are contemplated by the invention described herein below.
  • the present embodiments also preserve mobility of the facet joints.
  • Embodiments of the present invention accommodate the distinct anatomical structures of the spine, minimize further trauma to the spine, and obviate the need for invasive methods of surgical implantation.
  • Embodiments of the present invention also address spinal conditions that are exacerbated by spinal extension.
  • FIG. 1 shows a simplified diagram of a portion of the cervical spine, focusing on a cervical facet joint 1 formed between two adjacent cervical vertebrae.
  • the spinous processes 3 are located posteriorly and the vertebral bodies 5 are located anteriorly, and a nerve root canal 7 is visible.
  • Each vertebra has four posterior articulating surfaces: two superior facets and two inferior facets, with a superior facet from a lower vertebra and an inferior facet of an upper vertebra forming a facet joint on each lateral side of the spine.
  • the upward inclination of the superior articular surfaces of the facet joints allows for considerable flexion and extension, as well as for lateral mobility.
  • Each facet joint is covered by a dense, elastic articular capsule, which is attached just beyond the margins of the articular facets.
  • the capsule is large and looser in the cervical spine than in the thoracic and lumbar spine.
  • the inside of the capsule is lined by a synovial membrane which secretes synovial fluid for lubricating the facet joint.
  • the exterior of the joint capsule is surrounded by a capsular ligament. It is this ligament that may be pushed out of the way in the embodiments of the method for inserting the artificial facet joint, described herein.
  • FIG. 2 depicts cervical foraminal stenosis. From the drawing, the nerve root canal 7 is narrowed relative to the nerve root canal 7 depicted in FIG. 1 .
  • the spinal canal and/or intervertebral foramina also can be narrowed by stenosis. The narrowing can cause compression of the spinal cord and nerve roots.
  • FIG. 3A shows a first embodiment 100 of the present invention, which is meant to distract at least one facet joint, in order to increase the dimension of the neural foramen while retaining facet joint mobility.
  • the wedge-shaped embodiment or inter-facet spacer 100 is a wedge-shaped implant that can be positioned in the cervical facet joint 101 to distract the joint and reverse narrowing of the nerve root canal 107 .
  • the implant is positioned with the narrow portion of the wedge facing anteriorly.
  • implants in accordance with the present invention, and/or portions thereof can be fabricated from somewhat flexible and/or deflectable material.
  • the implant and/or portions thereof can be made out of a polymer, such as a thermoplastic.
  • the implant can be made from polyketone, known as polyetheretherketone (“PEEK”).
  • PEEK polyetheretherketone
  • the implant can be made from PEEK 450G, which is an unfilled PEEK approved for medical implantation available from Victrex of Lancashire, Great Britain. Other sources of this material include Gharda located in Panoli, India.
  • PEEK has the following approximate properties: Property Value Density 1.3 g/cc Rockwell M 99 Rockwell R 126 Tensile Strength 97 MPa Modulus of Elasticity 3.5 GPa Flexural Modulus 4.1 GPa
  • the material specified has appropriate physical and mechanical properties and is suitable for carrying and spreading a physical load between the adjacent spinous processes.
  • the implant and/or portions thereof can be formed by extrusion, injection, compression molding and/or machining techniques.
  • the implant can comprise, at least in part, titanium or stainless steel, or other suitable implant material which is radiopaque, and at least in part a radiolucent material that does not show up under x-ray or other type of imaging.
  • the physician can have a less obstructed view of the spine under imaging, than with an implant comprising radiopaque materials entirely.
  • the implant need not comprise any radiolucent materials.
  • the material selected also can be filled.
  • other grades of PEEK are also available and contemplated, such as 30% glass-filled or 30% carbon-filled, provided such materials are cleared for use in implantable devices by the FDA, or other regulatory body.
  • Glass-filled PEEK reduces the expansion rate and increases the flexural modulus of PEEK relative to that unfilled PEEK.
  • the resulting product is known to be ideal for improved strength, stifffiess, or stability.
  • Carbon-filled PEEK is known to enhance the compressive strength and stiffness of PEEK and to decrease its expansion rate. Carbon-filled PEEK offers wear resistance and load-carrying capability.
  • the implant is manufactured from PEEK, available from Victrex.
  • PEEK polyetherketoneketone
  • the spacer also can be comprised of polyetherketoneketone (“PEKK”).
  • PEKK polyetherketoneketone
  • Other material that can be used include polyetherketone (“PEK”), polyetherketoneetherketoneketone (“PEKEKK”), and polyetheretherketoneketone (“PEEKK”), and generally a polyaryletheretherketone.
  • the embodiment 200 of the implant has a joint insert or inter-facet spacer 210 , also herein referred to as an artificial facet joint or inter-facet spacer, that is positioned in the cervical facet joint 101 .
  • the joint insert or inter-facet spacer 210 can be wedge-shaped with the narrow part of the wedge facing anteriorly.
  • the joint insert or inter-facet spacer 210 need not be wedge-shaped but can be of substantially uniform thickness, the thickness determined by an individual patient's need for distraction of the cervical facet joint 201 .
  • one objective of this embodiment is facet joint distraction, and joint mobility after implantation.
  • the joint insert 210 is continuous with a posterior sheath 220 bent at an angle from the joint insert or inter-facet spacer 210 to align substantially parallel with the bone.
  • the posterior sheath can lie against the lamina, preferably against the lateral mass.
  • the posterior sheath 220 can have a bore 230 which can accept a bone screw 240 .
  • the bore 230 can accept any other appropriate and/or equivalent fixation device capable of fixing the embodiment 200 to the spine.
  • the device is thereby affixed to the vertebra, preferably by fixing to the lateral mass.
  • FIG. 5 shows embodiment 300 , which is the use of two embodiments 200 , each fixed to one of two adjacent cervical vertebrae.
  • the implanted facet joint is distracted and joint mobility is retained.
  • a joint insert or inter-facet spacer 310 from each of the two implants is inserted and positioned in the cervical facet joint 301 .
  • the joint inserts 310 are substantially flat and parallel to each other and are not wedge-shaped.
  • the joint inserts or inter-facet spacers 310 can together define a wedge-shaped insert that is appropriate for the patient.
  • the two joint inserts or inter-facet spacers 310 combined can have, by way of example, the shape of the joint insert or inter-facet spacers 210 in FIG. 4 .
  • Embodiment 300 then can be fixed to the spine with a screw 340 or any other appropriate fixation device, inserted through a bore 330 in the posterior sheath 320 .
  • the posterior sheath 320 can be threaded to accept a screw.
  • the screw can be embedded in the lamina, preferably in the lateral mass, where possible.
  • FIG. 6 depicts a cervical spine lordosis.
  • FIG. 7 demonstrates an embodiment 400 which contemplates positioning two implants to correct for this spinal abnormality while retaining facet joint mobility.
  • the joint insert or inter-facet spacer 410 of each implant is shaped so that it is thicker at its anterior portion.
  • the implants can be shaped to be thicker at the posterior ends, for example as depicted in FIG. 3A .
  • each implant is bent at an angle from the joint insert or inter-facet spacer 410 to be positioned adjacent to the lateral mass and/or lamina, and has a bore 430 to accept a screw 440 or other appropriate and/or equivalent fixation means to fix the embodiment 400 to the spine, preferably to the lateral mass.
  • the placement of two joint inserts or inter-facet spacers 410 in the cervical facet joint 401 distracts the facet joint, which shifts and maintains the vertebrae into a more anatomical position to preserve the physiology of the spine.
  • FIG. 8 shows a further embodiment 500 of the implant of the invention, wherein the joint insert or inter-facet spacer 510 has a keel 550 on an underside of the joint insert or inter-facet spacer 510 .
  • the keel 550 can be made of the same material or materials set forth above. The surfaces of the keel 550 can be roughened in order to promote bone in growth to stabilize and fix the implant 500 .
  • the keel 550 can be coated with materials that promote bone growth such as, for example, bone morphogenic protein (“BMP”), or structural materials such as hyaluronic acid “HA,” or other substances which promote growth of bone relative to and into the keel 550 .
  • BMP bone morphogenic protein
  • HA hyaluronic acid
  • the keel 550 can be embedded in the facet bone, to facilitate implant retention.
  • the keel 550 can be placed into a channel in the facet bone.
  • the channel can be pre-cut.
  • Teeth (not shown), preferably positioned posteriorly, also may be formed on the keel 550 for facilitating retention of the implant 500 in the cervical facet joint 501 .
  • the joint insert or inter-facet spacer 510 can be substantially flat or wedge-shaped, depending upon the type of distraction needed, i.e., whether distraction is also necessary to correct abnormal curvature or lack of curvature in the cervical spine. Because the joint is not fused, mobility is retained, as with the embodiments described above and herein below.
  • FIG. 9 illustrates that a further embodiment 600 of the implant of the invention can have both screw fixation and a keel 650 for stability and retention of the implant 600 .
  • the joint insert or inter-facet spacer 610 is continuous with a posterior sheath 620 having a bore hole 630 to accept a screw 640 which passes through the bore 630 and into the bone of the vertebrae, preferably into the lateral mass, or the lamina.
  • the bore 630 can be threaded or not threaded where it is to accept a threaded screw or equivalent device. Alternatively, the bore 630 need not be threaded to accept a non-threaded equivalent device.
  • the keel 650 is connected with the joint insert or inter-facet spacer 610 and embeds in the bone of the cervical facet joint 601 to promote implant retention.
  • FIG. 10 A further alternative embodiment 700 is illustrated in FIG. 10 .
  • the joint insert 710 has on a lower side at least one tooth 760 .
  • a plurality of teeth 760 is preferable.
  • the teeth 760 are able to embed in the bone of the cervical facet joint 701 to facilitate retention of the implant 700 in the joint 701 .
  • the teeth 760 can face in a direction substantially opposite the direction of insertion, for retention of the implant 700 .
  • the joint insert or inter-facet spacer 710 can be wedge-shaped or substantially even in thickness, depending upon the desired distraction. Because the implant distracts and is retained without fusion, facet joint mobility is retained.
  • FIG. 11 depicts a further embodiment 800 of the implant of the invention.
  • the joint insert or inter-facet spacer 810 is continuous with a posterior sheath 820 having a bore 830 for accepting a fixation device 840 , as described above.
  • the fixation device 840 can be a screw which fits into a threaded bore 830 ; alternatively, the fixation device 830 can be any other compatible and appropriate device.
  • This embodiment 800 further combines at least one tooth 860 on an underside of the joint insert or inter-facet spacer 810 with the posterior sheath 820 , bore 830 and fixation device 840 to address fixation of the implant 800 in a cervical facet joint 801 .
  • the implant 800 can have a plurality of teeth 860 on the underside of the joint insert or inter-facet spacer 810 .
  • FIG. 12 shows yet another embodiment 900 of an implant of the present invention.
  • the joint inserts or inter-facet spacers 910 of two implants 900 are positioned in a cervical facet joint 901 .
  • the joint inserts or inter-facet spacers 910 can be wedge-shaped as needed to restore anatomical curvature of the cervical spine and to distract, or the joint inserts or inter-facet spacers 910 can be of substantially uniform thickness.
  • the implants 900 each comprise a joint insert or inter-facet spacer 910 with an outer surface 970 that interacts with the bone of the cervical facet joint 901 .
  • the surface 970 that interacts with the bone is the upper surface 970 and on the lower implant 900 , the surface 970 that interacts with the bone is the lower surface 970 .
  • Each surface 970 can comprise a bone in growth surface 980 to create a porous surface and thereby promote bone in growth and fixation.
  • One such treatment can be with plasma spray titanium, and another, with a coating of sintered beads.
  • the implant 900 can have casted porous surfaces 970 , where the porous surface is integral to the implant 900 .
  • the surfaces 970 can be roughened in order to promote bone in growth into these defined surfaces of the implants 900 .
  • the surfaces 970 can be coated with materials that promote bone growth such as for example bone morphogenic protein (“BMP”), or structural materials such as hyaluronic acid (“HA”), or other substances which promote growth of bone on other external surfaces 970 of the implant 900 .
  • BMP bone morphogenic protein
  • HA hyaluronic acid
  • FIG. 13 depicts yet another embodiment 1000 of the implant of the present invention.
  • the joint inserts or inter-facet spacers 1010 of two implants 1000 are positioned in a cervical facet joint 1001 .
  • the joint inserts or inter-facet spacers 1010 can be wedge-shaped as needed to restore anatomical curvature of the cervical spine and to distract, or the joint inserts or inter-facet spacers 1010 can be of substantially uniform thickness.
  • the implants 1000 each comprise a joint insert or inter-facet spacer 1010 with an outer surface 1070 that interacts with the bone of the cervical facet joint 1001 .
  • each outer surface 1070 can comprise a bone in growth surface 1080 to create a porous surface and thereby promote bone in growth and fixation, without facet joint fusion and loss of mobility.
  • the bone in growth surface 1080 can be created with plasma spray titanium, and/or with a coating of sintered beads.
  • the implant 1000 can have casted porous surfaces 1070 , where the porous surface is integral to the implant 1000 .
  • the surfaces 1070 can be roughened in order to promote bone in growth into these defined surfaces of the implants 1000 .
  • the surfaces 1070 can be coated with materials that promote bone growth such as for example BMP, or structural materials such as HA, or other substances which promote growth of bone on other external surfaces 1070 of the implant 1000 .
  • the implant 1000 can have a posterior alignment guide 1090 .
  • the posterior alignment guides 1090 of each implant 1000 can be continuous with the joint inserts or inter-facet spacers 1010 .
  • the posterior alignment guides substantially conform to the bone of the vertebrae when the joint inserts or inter-facet spacers 1010 are inserted into the cervical facet joint 1001 .
  • the posterior alignment guides 1090 are used to align the implants 1000 so that the joint inserts 1010 contact each other and not the bones of the cervical facet joint 1001 when the joint inserts 1010 or inter-facet spacers are positioned in the cervical facet joint 1001 .
  • FIG. 14 depicts a further embodiment 1100 of the implant of the present invention.
  • the joint inserts 1110 of two implants 1100 are inserted into the cervical facet joint 1101 .
  • Each of the joint inserts or inter-facet spacers 1110 is continuous with a cervical facet joint extender or facet-extending surface 1192 .
  • the bone contacting surfaces 1170 of the joint inserts or inter-facet spacers 1110 are continuous with, and at an angle to, the bone contacting surfaces 1193 of the cervical facet joint extenders 1192 , so that the cervical facet joint extenders 1192 conform to the bones of the vertebrae exterior to the cervical facet joint 1101 .
  • the conformity of the cervical facet joint extenders 1192 is achieved for example by forming the cervical facet joint extenders 1192 so that when the join inserts or inter-facet spacers 1110 are positioned, the cervical facet joint extenders 1192 curve around the bone outsider the cervical facet joint 1101 .
  • the cervical facet joint extenders have a second surface 1184 that is continuous with the joint articular surfaces 1182 of the joint inserts or inter-facet spacers 1110 .
  • the second surfaces 1184 extend the implant 1100 posteriorly to expand the joint articular surfaces 1182 and thereby to increase contact and stability of the spine at least in the region of the implants 1100 . It is to be understood that such facet joint extenders 1192 can be added to the other embodiments of the invention described and depicted herein.
  • each of two implants 1200 has a joint insert or inter-facet spacer 1210 positioned in a cervical facet joint 1201 .
  • the joint inserts or inter-facet spacers 1210 can be wedge-shaped as needed to restore anatomical curvature of the cervical spine and to distract, or the joint inserts or inter-facet spacers 1210 can be of substantially uniform thickness.
  • the implants 1200 each comprise a joint insert 1210 with an outer surface 1270 that interacts with the bone of the cervical facet joint 1001 .
  • each outer surface 1270 can comprise a bone in growth surface 1280 to create a porous surface and thereby promote bone in growth and fixation.
  • the bone in growth surface 1280 can be created with plasma spray titanium, and/or with a coating of sintered beads.
  • the implant 1200 can have casted porous surfaces 1270 , where the porous surface is integral to the implant 1200 .
  • the surfaces 1270 can be roughened in order to promote bone in growth into these defined surfaces of the implants 1200 .
  • the surfaces 1270 can be coated with materials that promote bone growth such as for example BMP, or structural materials such as HA, or other substances which promote growth of bone on other external surfaces 1270 of the implant 1200 .
  • Screw fixation or other appropriate fixation also can be used with implants 1200 for fixation in the cervical facet joint 1201 .
  • the joint insert or inter-facet spacer 1210 is continuous with a posterior sheath 1220 bent at an angle from the joint insert or inter-facet spacer 1210 to align substantially parallel with the bone, preferably the lateral mass or lamina.
  • the posterior sheath 1220 can have a bore 1230 which can accept a bone screw 1240 , preferably into the lateral mass or lamina.
  • the bore 1230 can accept any other appropriate and/or equivalent fixation means for fixing the embodiment 1200 to the spine.
  • FIG. 16 depicts a further preferred embodiment of the present invention.
  • two joint inserts or inter-facet spacers 1310 are positioned in the cervical facet joint 1301 .
  • the joint inserts each have outer surfaces 1370 that interact with the bone of the vertebrae forming the cervical facet joint.
  • These outer surfaces 1370 of the embodiment 1300 can be treated to become bone in growth surfaces 1380 , which bone ingrowth surfaces 1380 contribute to stabilizing the two joint inserts or inter-facet spacers 1310 of the implant 1300 .
  • the bone ingrowth surface 1380 can be created with plasma spray titanium, and/or with a coating of sintered beads.
  • the implant 1300 can have casted porous surfaces 1370 , where the porous surface is integral to the implant 1300 .
  • the surfaces 1370 can be roughened in order to promote bone ingrowth into these defined surfaces of the implants 1300 .
  • the surfaces 1370 can be coated with materials that promote bone growth such as for example BMP, or structural materials such as HA, or other substances which promote growth of bone on other external surfaces 1370 of the implant 1300 . This fixation stabilizes the implant 1300 in the facet joint without fusing the joint, and thus the implant preserves joint mobility, while accomplishing distraction and increasing foraminal dimension.
  • articular inner surfaces 1382 of the implants 1300 can be formed from a metal and polyethylene, the material allowing flexibility and providing for forward bending/flexion and backward extension of the cervical spine.
  • the embodiment 1300 of FIG. 16 can be made in at least two configurations.
  • the first configuration includes a flexible spacer 1382 made, by way of example, using polyethylene or other suitable, flexible implant material.
  • the flexible spacer 1382 can be permanently affixed to the upper and lower joint insert or inter-facet spacer 1310 .
  • the spacer 1382 can be flat or wedge-shaped or have any other shape that would correct the curvature of the spine.
  • the spacer 1382 can be affixed to only the upper insert or inter-facet spacer 1310 or to only the lower insert 1310 .
  • a spacer 1382 can be affixed to each of an upper insert or inter-facet spacer 1310 and a lower insert or inter-facet spacer 1310 with the upper insert or inter-facet spacer 1310 and the lower insert or inter-facet spacer 1310 being separate units.
  • FIG. 17 shows a further preferred embodiment of the implant of the present invention.
  • the implant has a roller 1496 mounted on a joint insert or inter-facet spacer 1410 , the roller being a further means of preserving joint mobility while accomplishing distraction.
  • Both the roller 1496 and the joint insert or inter-facet spacer 1410 are positioned in the cervical facet joint 1401 .
  • the joint insert or inter-facet spacer 1410 as in other embodiments has a bone-facing surface 1470 and joint articular surface 1482 .
  • the bone-facing surface 1470 can interact with the lower bone of the cervical facet joint 1401 .
  • the bone-facing surface can interact with the upper bone of the cervical facet joint 1401 .
  • roller 1496 rotates in a cavity in the joint insert 1410 , and interacts with the top bone of the cervical facet joint 1401 .
  • the roller 1496 rotates in a cavity in the joint insert or inter-facet spacer 1410 and interacts with the lower bone of the cervical facet joint 1401 .
  • the rotation of the roller 1496 allows flexion and extension of the cervical spine.
  • a roller such as roller 1496 can be secured to an upper and a lower insert such as inserts 410 in FIG. 7 .
  • a plurality of rollers 1496 also is possible.
  • FIG. 19 depicts a further embodiment of the implant of the present invention.
  • two implants 1500 are implanted in the cervical facet joint 1501 .
  • Screw fixation or other appropriate fixation is used with implants 1500 for fixation in the cervical facet joint 1501 .
  • the joint insert or inter-facet spacer 1510 is continuous with a posterior sheath 1520 bent at an angle from the joint insert or inter-facet spacer 1510 to align substantially parallel with the bone, preferably the lateral mass or lamina.
  • the posterior sheath 1520 of each implant 1500 can have a bore 1530 which can accept a bone screw 1540 , preferably into the lateral mass or lamina.
  • the bore 1530 can accept any other appropriate and/or equivalent fixation means for fixing the embodiment 1500 to the spine.
  • the head of the screw 1540 in each posterior sheath 1520 of each implant 1500 has a groove 1598 or other mechanism for retaining an elastic band 1597 .
  • the elastic band 1597 is looped around each of the two screws 1540 to restrain movement of the cervical spine without eliminating facet joint mobility.
  • the band 1597 preferably can restrain flexion and lateral movement.
  • the elastic band 1597 can be made of a biocompatible, flexible material.
  • FIG. 20 shows an alternative to use of an elastic band as in FIG. 19 .
  • the elastic band is replaced with a spring restraint 1699 , which extends between the heads of two screws 1640 , one screw fixing each of two implants 1600 in the cervical facet joint 1601 .
  • FIG. 21 shows another alternative to using an elastic band and/or a spring as in FIGS. 19 or 20 .
  • magnets 1795 are used for restraint between the two screws 1740 .
  • the magnet 1795 can either be comprised of two opposing magnetic fields or two of the same magnetic fields to operate to restrain movement.
  • the head of one of the two screws 1740 is magnetized, and the head of the other screw 1740 is magnetized with either the same or opposite field. If the magnets 1795 have the same polarity, the magnets 1795 repel each other and thus limit extension. If the magnets 1795 have opposite polarities, the magnets 1795 attract each other and thus limit flexion and lateral movement.
  • FIGS. 22A-24B depict a further embodiment 1800 of the implant of the present invention.
  • a facet joint spacer (or insert) or inter-facet spacer (or insert) 1810 is connected with a lateral mass plate (also referred to as an anchoring palte) 1820 with a hinge 1822 .
  • the hinge 1822 allows the lateral mass plate 1820 to bend at a wide range of angles relative to the artificial facet joint and preferably at an angle of more than 90 degrees, and this flexibility facilitates positioning and insertion of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1810 into a patient's facet joint, the anatomy of which can be highly variable among individuals.
  • the hinge 1822 further facilitates customizing the anchoring of the implant, i.e., the positioning of a fixation device.
  • the hinge enables positioning of the lateral mass plate 1820 to conform to a patient's cervical spinal anatomy, and the lateral mass plate 1820 accepts a fixation device to penetrate the bone.
  • the facet joint spacer (or insert) or inter-facet spacer (or insert) 1810 can be curved or rounded at a distal end 1812 ( FIG. 23A ), and convex or dome-shaped on a superior surface 1813 to approximate the shape of the bone inside the facet joint.
  • the inferior surface 1815 can be flat or planar. Alternatively, the inferior surface 1815 can be concave. As another alternative, the inferior surface 1815 can be convex.
  • the lateral mass plate 1820 when implanted in the spine, is positioned outside the facet joint, preferably against the lateral mass or against the lamina.
  • the lateral mass plate 1820 has a bore 1830 therethrough.
  • the bore 1830 can accept a bone screw 1840 , also referred to as a lateral mass screw, to secure the lateral mass plate 1820 preferably to the lateral mass or alternatively to another part of the spine, and thus to anchor the implant.
  • the lateral mass screw 1840 preferably has a hexagonal head to accept an appropriately-shaped wrench. As described below, the head accepts a compatible probe 1826 from a locking plate 1824 .
  • the locking plate 1824 includes a keel 1828 with a wedge shaped distal end to anchor the implant, preferably in the lateral mass or in the lamina, outside the facet joint and to prevent rotation of the lateral mass plate 1820 and the locking plate 1824 .
  • the keel 1828 aligns with a groove 1823 through an edge of the lateral mass plate 1820 to guide and align the keel 1828 as the keel 1828 cuts into a vertebra.
  • the locking plate 1824 includes a probe 1826 that fits against the head of the lateral mass screw 1840 .
  • the locking plate further includes a bore 1831 that can accept a machine screw (not shown) which passes through to an aligned bore 1829 in the lateral mass plate 1820 to hold the locking plate 1824 and the lateral mass plate 1820 together without rotational displacement relative to each other.
  • the locking plate 1824 thus serves at least two functions: (1) maintaining the position of the lateral mass screw 1840 with the probe 1826 , so that the screw 1840 does not back out; and (2) preventing rotation of the implant with the keel 1828 and machine screw relative to the cervical vertebra or other vertebrae.
  • the locking plate 1824 can include a probe with barbs that can be inserted into a port in the lateral mass plate. The barbs can become engaged in ribs that define the side walls of the port in the lateral mass plate.
  • the lateral mass plate 1920 includes a recessed area 1922 for receiving the locking plate 1924 so that the locking plate 1924 is flush with the upper surface 1925 of the lateral mass plate 1920 when the probe 1926 is urged against the lateral mass screw 1940 and the keel 1928 is inserted into the lateral mass or the lamina of the vertebra.
  • the shape and contours of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 can facilitate insertion of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 into the cervical facet joint.
  • the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 has a rounded distal end 1912 .
  • the distal end 1912 is tapered in thickness to facilitate insertion.
  • the tapered distal end 1912 meets and is continuous with a proximal mid-section 1916 which, in this preferred embodiment, has a uniform thickness, and is connected flexibly, preferably with a hinge 1922 , to the lateral mass plate 1920 , as described above.
  • the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 is curved downward, causing a superior surface 1913 of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 to be curved.
  • the curve can cause the superior surface 1913 to be convex, and the convexity can vary among different implants 1900 to suit the anatomical structure of the cervical facet joint(s) of a patient.
  • An inferior surface 1915 accordingly can be preferably concave, flat, or convex.
  • the curved shape of the implant can fit the shape of a cervical facet joint, which is comprised of an inferior facet of an upper vertebra and a superior facet of a lower adjacent vertebra.
  • the convex shape of the superior surface 1913 of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 fits with a concave shape of the inferior facet of the upper cervical vertebrae.
  • the concave shape of the inferior surface 1915 of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 fits with the convex shape of the superior facet of the cervical vertebrae.
  • the degree of convexity and concavity of the facet joint spacer (or insert) or inter-facet spacer (or insert) inferior and superior surfaces can be varied to fit a patient's anatomy and the particular pairing of adjacent cervical vertebrae to be treated.
  • a less-curved facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 can be used where the patient's cervical spinal anatomy is sized (as described below) and found to have less convexity and concavity of the articular facets.
  • the input for the right and left facet joint will be similarly shaped.
  • the width of the mid-section 1916 is from 1.5 mm to 2.5 mm.
  • FIGS. 22A-24B is similar to the embodiment shown in FIGS. 25A, 25B . Accordingly the remaining elements on the 1900 series of element numbers is preferably substantially similar to the described elements in the 1800 series of element numbers, as set forth above. Thus, by way of example, elements 1923 , 1928 , 1929 and 1930 are similar, respective elements 1823 , 1828 , 1829 and 1830 .
  • FIG. 30 is a flow chart of the method of insertion of an implant of the invention.
  • the embodiment 1800 or 1900 of the present invention preferably is inserted in the following manner (only elements of the embodiment 1800 will be set forth herein, for purposes of the written description of a method of the invention).
  • a sizing tool 2200 (see FIGS. 29 A-C) can be inserted to select the appropriate size of an implant of the invention for positioning in the cervical facet joint. This step may be repeated as necessary with, if desired, different sizes of the tool 2200 until the appropriate size is determined. This sizing step also distracts the facet joint and surrounding tissue in order to facilitate insertion of the implant.
  • the natural or artificial facet joint spacer or inter-facet spacer 1810 is urged between the facets into the facet joint.
  • the facet itself is somewhat shaped like a ball and socket joint. Accordingly, in order to accommodate this shape, the natural or artificial joint spacer or inter-facet spacer 1810 can have a rounded leading edge shaped like a wedge or tissue expander to cause distraction of the facet joint as the natural or natural or artificial facet joint spacer or inter-facet spacer spacer or inter-facet spacer is urged into the facet joint of the spine.
  • the natural or artificial facet joint spacer or inter-facet spacer 1810 also includes the convex surface 1813 in order to more fully accommodate the shape of the facet joint of the spine.
  • the lateral mass plate 1820 is pivoted downward about the hinge 1822 adjacent to the vertebrae and preferably to the lateral mass or to the lamina.
  • the lateral mass plate 1820 may be disposed at an angle relative to the natural or artificial facet joint spacer or inter-facet spacer 1810 for a representative spine configuration. It is to be understood that as this embodiment is hinged the final position of the lateral mass plate 1820 relative to the natural or artificial facet joint spacer or inter-facet spacer 1810 will depend on the actual spine configuration.
  • embodiments of the invention can be made without a hinge, as long as the connection between the natural or artificial facet joint spacer or inter-facet spacer and the lateral mass plate is flexible enough to allow the lateral mass plate to be bent relative to the natural or artificial facet joint spacer or inter-facet spacer in order to fit the anatomy of the patient.
  • a bore can be drilled in the bone to accommodate the bone screw 1824 .
  • the screw 1824 can be self-tapping.
  • the screw is then placed through the bore 1830 and secured to the bone, preferably the lateral mass or the lamina, thereby holding the natural or artificial facet joint spacer or inter-facet spacer 1810 in place.
  • the locking plate 1824 is positioned over the lateral mass plate 1820 . So positioned, the probe 1826 is positioned through the bore 1830 and against the head of the bone screw to keep the bone screw from moving.
  • the keel 1828 having a sharp chisel-shaped end, preferably can self-cut a groove in the bone so that the keel 1828 is locked into the bone as the keel 1828 is aligned by, and received in, a groove 1831 of the lateral mass plate 1820 .
  • a groove can be pre-cut in the bone to receive the keel 1828 .
  • the bore 1829 of the locking plate 1824 aligns with the threaded bore 1831 of the lateral mass plate 1820 and a machine screw can be inserted to lock the locking plate relative to the lateral mass plate.
  • the implant is between the C 5 and C 6 vertebrae level, or the C 6 and C 7 vertebrae level. It is noted that two implants preferably will be implanted at each level between vertebrae. That is, an implant 1800 will be placed in a right facet joint and also in a left facet joint when viewed from a posterior view point.
  • This procedure can be used to increase or distract the foraminal area or dimension of the spine in an extension or in neutral position (without having a deleterious effect on cervical lordosis) and reduce the pressure on the nerves and blood vessels. At the same time this procedure preserves mobility of the facet joint.
  • FIGS. 26A-27B show a further embodiment of the implant of the invention, with the embodiment 2000 implanted in the cervical spine as depicted in FIGS. 27A and 27B .
  • the implant 2000 comprises a first natural or artificial facet joint spacer or inter-facet spacer 2010 and a second natural or artificial facet joint spacer or inter-facet spacer 2010 .
  • Each natural or artificial facet joint spacer or inter-facet spacer can have a distal end 2012 that is tapered or wedge-shaped in a way that facilitates insertion into the cervical facet joints on both sides of two adjacent cervical vertebrae at the same level.
  • the natural or artificial facet joint spacers or inter-facet spacers further can be dome-shaped, or convex on a superior surface 2013 , to approximate the shape of the cervical facets of the cervical facet joints.
  • the first and second natural or artificial facet joint spacer or inter-facet spacer s 2010 are bridged together by a collar 2015 .
  • the collar 2015 passes between the spinous processes of the adjacent cervical vertebrae.
  • the implant can preferably be “V” shaped or “boomerang” shaped.
  • the entire implant 2000 or the collar 2015 of the implant can be made of a flexible material such as titanium, so that it is possible to bend the collar 2015 so that it conforms preferably to the shape of the lateral mass or the lamina of the cervical vertebrae of the patient and thereby holds the implant in place with the natural or artificial facet joint spacer or inter-facet spacer s 2010 inserted in the cervical facet joints.
  • Bores 2029 are preferably are provided through implant 2000 adjacent to the natural or artificial facet joint spacer or inter-facet spacer 2010 respectively. These bores 2029 can receive bone screws to position the implant 2000 against the lateral mass or the lamina as shown in FIGS. 27A, 27B .
  • the description of the embodiment 2100 , in FIGS. 28A, 28B provide further details concerning the method of affixing the implant 2000 to the vertebrae.
  • the implant 2100 also can be made of PEEK or other materials as described herein.
  • Embodiment 2000 (the “boomerang” shape depicted in FIG. 27B ) further can have a locking plate as, for example, the locking plate 1824 in FIG. 22A .
  • the locking plate for embodiment 2000 can have the same features as locking plate 1824 , that is: (1) a probe 1826 that interacts with the bone screws to prevent the bone screws from backing out of the bone, the likely consequence of which would be displacement of the implant 2000 ; and (2) a keel 1828 with a chisel end to embed in the bone and thus to prevent rotational displacement of the implant.
  • a chisel may not serve the same purpose as with the embodiments set forth above, which lack a collar stabilized by two bone screws. Therefore, a locking plate on embodiment 2000 can be provided without a keel.
  • FIGS. 28A and 28B depict a further embodiment of the implant of the invention 2100 .
  • the collar 2115 can be made of a flexible material such as titanium, of a substantially inflexible material, or of other materials described herein. Substantial flexibility can also be derived from connecting a first natural or artificial facet joint spacer or inter-facet spacer 2110 with the collar 2115 using a first hinge 2117 , and connecting a second natural or artificial facet joint spacer or inter-facet spacer 2110 with the collar 2115 using a second hinge 2117 .
  • the collar 2115 can be pivoted downward to conform to a particular patient's cervical spinal anatomy. In other words, the degree of pivoting will vary among different patients, and the first hinge 2117 and second hinge 2117 allow the implant 2100 to accommodate the variance.
  • the collar 2115 can have a first bore 2129 inferior to the first hinge 2117 , and a second bore 2129 inferior to the second hinge 2117 .
  • a first bone screw penetrates the first bore 2130 and into the lateral mass or the lamina
  • the second bone screw penetrates the second bore 2130 and into the lateral mass or the lamina, the first and second bone screws serving to anchor the implant.
  • a bore, preferably in the lateral mass, can be drilled for the first bone screw and for the second bone screw.
  • the bone screws can be self-tapping.
  • a first locking plate similar to the plate 1924 ( FIG.
  • the first locking plate can block the first bone screw with a probe and the second locking plate can block to the second bone screw with a probe.
  • embodiments 2000 and 2100 also can be configured for accommodating treatment of cervical spinal stenosis and other cervical spine ailments where only a single cervical facet joint between adjacent vertebrae requires an implant, i.e., where treatment is limited to one lateral facet joint.
  • the collar 2015 , 2115 extends medially without extending further to join a second natural or artificial facet joint spacer or inter-facet spacer 2010 , 2110 .
  • the implant comprises a single hinge 2117 , and the collar 2115 has only one bore 2129 to accept one bone screw to secure the implant 2100 .
  • FIGS. 29 A-E depict a sizing and distracting tool 2200 of the invention.
  • Sizing tool 2200 has a handle 2203 and a distal head 2210 that is shaped as a natural or artificial facet joint spacer or inter-facet spacer (e.g., 1810 ) of an implant of the invention. That is, the head 2210 preferably will have essentially the same features as the natural or artificial facet joint spacer or inter-facet spacer 1810 , but the dimensions of the head 2210 will vary from one tool 2200 to the next, in order to be able to use different versions of the sizing tool 2200 to determine the dimensions of the cervical facet joint that is to be treated and then to select an appropriately-sized implant.
  • the head 2210 preferably can be used to distract the facet joint prior to the step of implanting the implant in the facet joint.
  • the head 2210 is rounded at the most distal point 2212 , and can be a tapered to facilitate insertion into a cervical facet joint.
  • the head 2210 also can have a slightly convex superior surface 2213 , the degree of convexity varying among different sizing tools 2200 in order to determine the desired degree of convexity of an implant to be implanted in the cervical facet joint.
  • the head 2210 may have a uniform thickness along a proximal mid-section 2216 .
  • the inferior surface 2215 preferably can be concave.
  • the proximal mid-section 2212 maybe convex on the superior surface 1813 without being uniform in thickness.
  • the inferior surface 2215 can be flat or planar.
  • the head also can be curved.
  • the head 2210 has a stop 2218 to prevent over-insertion of the head 2210 of the sizing tool 2200 into the facet joint.
  • the stop 2218 can be a ridge that separates the head 2210 from the handle 2203 .
  • the stop 2218 can be any structure that prevents insertion beyond the stop 2218 , including pegs, teeth, and the like.
  • Different sizing tools 2200 covering a range of dimensions of the head 2210 can be inserted successively into a cervical facet joint to select the appropriate size of an implant to position in the cervical spine, with the appropriate convexity and concavity of the natural or artificial facet joint spacer or inter-facet spacer. Each preferably larger head also can be used to distract the facet joint.
  • FIG. 31A depicts a posterior view of a further embodiment 2300 of the implant of the invention.
  • Embodiment 2300 as well as all of the embodiments herein, can benefit from some or all of the advantages described herein with regard to the other embodiments described herein.
  • embodiment 2300 has a natural or artificial facet joint spacer or inter-facet spacer 2310 that can have a tapered or thinned distal end 2312 so that the distal end 2312 facilitates insertion of the natural or artificial facet joint spacer or inter-facet spacer 2310 into a cervical facet joint.
  • the distal end 2312 can be rounded, as seen in the plan view of FIG. 31A , in order to conform to the roundness of the facet joint.
  • the natural or artificial facet joint spacer or inter-facet spacer 2310 further can be curved so that a superior surface 2313 of the natural or artificial facet joint spacer or inter-facet spacer 2310 is convex, and an inferior surface 2315 is concave, to approximate the natural shape of the cervical facet joint that is to receive the implant 2300 .
  • the curve can have a uniform thickness, or it can have a varied thickness.
  • the lateral edges of the natural or artificial facet joint spacer or inter-facet spacer 2310 are curved or rounded, for distribution of load-bearing stress.
  • the natural or artificial facet joint spacer or inter-facet spacer 2310 also can be made of a flexible, biocompatible material, such as PEEK, to maintain joint mobility and flexibility.
  • the natural or artificial facet joint spacer or inter-facet spacer 2310 is connected flexibly with a lateral mass plate 2320 , the flexible connection preferably being a hinge 2322 .
  • the implant 2300 is substantially hour-glass shaped. This shape, as well as the shape of FIG. 32 , will be discussed further below.
  • the hinge 2322 is narrower than the natural or artificial facet joint spacer or inter-facet spacer 2310 , with the hinge 2322 sitting at substantially the isthmus 231 7 between the natural or artificial facet joint spacer or inter-facet spacer 2310 and the lateral mass plate 2320 .
  • the curved edges, or fillets, about the hinge 2322 serve to distribute more evenly the load-bearing stress on the implant 2300 , and thus prevent concentrating the stress about the edges.
  • the hinge 2322 allows the implant 2300 to bend at the hinge 2322 , bringing a lateral mass plate 2320 adjacent to the lateral mass and/or lamina of the patient's spine, and to conform to a particular patient's anatomy.
  • the lateral mass plate 2320 is made of a biocompatible flexible material, preferably titanium or any other biocompatible flexible material as described herein, for example PEEK, that will support the use of bone screws and other hardware, as described below.
  • the lateral mass plate 2320 bends downward at the hinge 2322 over a wide range of angles relative to the natural or artificial facet joint spacer or inter-facet spacer 2310 , and preferably at an angle of more than 90 degrees, and this flexibility facilitates positioning and insertion of the natural or artificial facet joint spacer or inter-facet spacer.
  • This flexibility of the lateral mass plate 2320 relative to the natural or artificial facet joint spacer or inter-facet spacer 2310 further facilitates positioning of the lateral mass plate relative to the lateral mass and/or the lamina of the patient's spine.
  • a first bone screw such as bone screw 1840 , can be inserted through a first bore 2330 through the lateral mass plate 2320 and embedded into the bone of the lateral mass of the cervical vertebra.
  • the lateral mass plate 2320 further comprises a second bore 2329 which is preferably positioned medially, relative to the first bore 2330 .
  • the second bore 2329 in the lateral mass plate 2320 can be positioned either to the left or to the right of the first bore 2330 .
  • the position of the second bore 2329 will depend upon whether the implant 2300 is intended to be inserted into a cervical facet joint on the left or right side of a patient. Specifically, an implant 2300 to be inserted into a right-side cervical facet joint (i.e., the patient's rights side) will have a second bore 2329 positioned to the left of the first bore 2330 as in FIG.
  • the second bore 2329 through the lateral mass plate 2320 is adapted to accept a second screw 2390 ( FIG. 31B ), which preferably is a locking screw with a chisel point 2391 .
  • the locking screw 2390 is received by the second bore 2329 and the chisel point 2391 self-cuts a bore into the bone.
  • the locking screw 2390 preferably is inserted through the second bore 2329 and embedded in the bone, after the bone screw is embedded in the bone through the first bore 2330 .
  • the position of the second bore 2329 i.e., medial to the first bore 2330 , positions the locking screw 2390 so that it embeds in stronger bone tissue than if the second bore 2329 were located more laterally.
  • the locking screw in combination with the bone screw, prevents rotational and/or backward displacement of the implant 2300 .
  • the head 2392 of the locking screw 2390 aligns with the head of the first bone screw in the first bore 2330 , blocking the head of the first bone screw to prevent the first bone screw from backing out of the bone of the vertebra and the first bore 2330 .
  • FIG. 32 depicts a further embodiment 2400 of the implant of the invention, from a posterior view.
  • Embodiment 2400 is adapted to be implanted in a manner that preserves the anatomy of the cervical facet joint, in particular, the soft tissues around the cervical facet joint, including the joint capsule.
  • Implant 2400 like implant 2300 and other implants disclosed above, has a natural or artificial facet joint spacer or inter-facet spacer 2410 , flexibly connected, preferably by a hinge 2422 , to a lateral mass plate 2420 .
  • the implant 2400 including the natural or artificial facet joint spacer or inter-facet spacer 2410 and the hinge 2422 is substantially “P” shaped. As explained below, its “P” shape assists in the insertion of the implant 2400 into the facet joint with most of the facet capsule and facet capsule ligament and other soft tissue associated with the facet joint still left intact.
  • the natural or artificial facet joint spacer or inter-facet spacer can have a superior surface 2413 of the natural or artificial facet joint spacer or inter-facet spacer 2410 that is convex, and an inferior surface 2415 that is concave, or any appropriate shaping to approximate the natural shape of the cervical facet joint that is to receive the implant 2400 .
  • the thickness of the natural or artificial facet joint spacer or inter-facet spacer 2410 can be uniform, or varied.
  • the natural or artificial facet joint spacer or inter-facet spacer 2410 also can be made of a flexible, biocompatible material, such as PEEK, to maintain joint mobility and flexibility.
  • the hinge 2422 can have smooth, rounded edges, for distribution of load stress, as disclosed above.
  • Other features and advantages of the other embodiments can be, if desired, incorporated into the design of the embodiment of FIG. 32 .
  • the natural or artificial facet joint spacer or inter-facet spacer 2410 further can have a tapered or thinned edge 2412 so that the edge 2412 facilitates insertion of the natural or artificial facet joint spacer or inter-facet spacer 2410 into a cervical facet joint.
  • the edge 2412 can be curved.
  • the thinned edge 2412 of the natural or artificial facet joint spacer or inter-facet spacer 2410 preferably is not at the distal end of the natural or artificial facet joint spacer or inter-facet spacer 2400 as is the thinned edge 2312 of the natural or artificial facet joint spacer or inter-facet spacer 2300 ; rather, the thinned edge 2412 preferably is positioned laterally, toward the hinge 2422 of the implant 2400 .
  • the thinned edge 2412 coincides substantially with a lateral curvature 2440 of the natural or artificial facet joint spacer or inter-facet spacer 2410 , which is pronounced relative to the curvature on the medial side of the implant 2400 , i.e., a “P” shape.
  • the curved part of the head of the “P” 2440 corresponds to the thinned edge 2412 , and serves as the leading edge of the implant 2400 to begin insertion of the natural or artificial facet joint spacer or inter-facet spacer 2410 into a cervical facet joint, preferably through an incision in the soft tissue of the facet joint.
  • the “P” shape narrows at isthmus 2417 where the natural or artificial facet joint spacer or inter-facet spacer 2410 that is joined by the hinge 2422 with the lateral mass plate 2420 .
  • the smooth or rounded edges or fillets serve to distribute stresses on the implant 2400 .
  • the above described “P” shape of implant 2400 allows the implant 2400 to be pivoted into place into a facet joint as described below.
  • the thinned edge 2412 and leading lateral curvature 2440 of the natural or artificial facet joint spacer or inter-facet spacer 2410 are adapted to facilitate urging implant 2400 into the cervical facet joint, through the incision in the joint capsule.
  • the implant 2400 then is pivoted into position so that the lateral mass plate 2420 can be bent downward, relative to the natural or artificial facet joint spacer or inter-facet spacer 2410 , to align with and lie adjacent to the lateral mass and/or the lamina.
  • the lateral mass plate 2420 is then fastened to the bone.
  • the lateral mass plate 2420 of implant 2400 is flexibly connected, preferably by the smooth-edged hinge 2422 , to the natural or artificial facet joint spacer or inter-facet spacer 2410 at the narrow lower part of the natural or artificial facet joint spacer or inter-facet spacer.
  • the lateral mass plate 2420 is made of a biocompatible flexible material, preferably titanium or any other biocompatible flexible material such as PEEK that will support the use of bone screws and other hardware, as described below.
  • the lateral mass plate 2420 bends downward at a wide range of angles relative to the natural or artificial facet joint spacer or inter-facet spacer 2410 , and preferably at an angle of more than 90 degrees.
  • the flexibility of the lateral mass plate 2420 relative to the natural or artificial facet joint spacer or inter-facet spacer 2410 further facilitates positioning of the lateral mass plate 2420 relative to the lateral mass and/or the lamina of the patient's spine.
  • the lateral mass plate 2420 has first bore 2430 , which is adapted to receive a bone screw 2440 , to help anchor implant 2400 in position.
  • the lateral mass plate 2420 further includes a second bore 2429 adapted to be positioned medially, relative to the first bore 2430 , as disclosed above for implant 2300 .
  • the position of the second bore 2429 when viewing implant 2400 from a posterior perspective ( FIG. 32 ), will depend upon whether implant 2400 is intended to be implanted into a left-side or right-side cervical facet joint of a patient.
  • implant 2400 with the second bore 2429 positioned to the left of the first bore 2430 is intended to be implanted in a right-side cervical facet joint of a patient, as depicted in FIG. 32
  • an implant 2400 with a second bore 2429 positioned to the right of the first bore 2430 is intended to be implanted in a left-side cervical facet joint of a patient.
  • the second bore 2429 through the lateral mass plate 2420 is adapted to receive a second screw 2490 with head 2492 , which preferably is a locking screw with a chisel point, such as screw 2390 .
  • the function and purpose of the bone screw disposed through bore 2430 and the locking screw disposed through bore 2429 are as described above with respect to the implant 2300 .
  • the present invention further includes a method of implanting the implant 2400 ( FIGS. 33A, 33B ).
  • a facet joint is accessed and an incision or a pair of incisions is made in the capsular ligament, the joint capsule, and the synovial membrane so that the thinned edge 2412 of the implant 2400 can be urged into the cervical facet joint through these tissues.
  • the capsular ligament and the joint capsule and other soft tissues around the cervical facet joint are allowed to remain substantially intact, except for the small incision, and will be sutured and allowed to heal around the implant 2400 .
  • the cervical facet joint can be distracted prior to urging the curved section 2440 with the thinned edge 2412 of the natural or artificial facet joint spacer or inter-facet spacer 2410 into the cervical facet joint.
  • implant 2400 is pivoted, preferably about 90 degrees, so that the second bore 2429 is placed medially relative to the first bore 2430 . This allows the natural or artificial facet joint spacer or inter-facet spacer 2410 to be positioned in the facet joint.
  • the overall size, including the isthmus 2417 , of the artificial fact joint 2410 , as that of 2310 , can be somewhat smaller than in prior embodiments to allow the natural or artificial facet joint spacer or inter-facet spacer to be positioned within the edges of the facet joint with the joint capsule substantially intact.
  • the lateral mass plate 2420 then can be bent downward about the hinge 2422 into position adjacent the lateral mass or lamina of the spine of the patient, which position will depend upon the anatomy of an individual patient's cervical spine.
  • a first bone screw can be inserted through the first bore 2430 through the lateral mass plate 2420 and become embedded into the bone of the lateral mass of the cervical vertebra to anchor the implant 2400 .
  • a locking screw is inserted through the second bore 2429 of the lateral mass plate 2420 , the second bore 2429 medial to the first bore 2430 .
  • the locking screw has a chisel end that allows the locking screw to dig into the bone without use of a tool to pre-cut a bore.
  • a bore can be pre-cut and a locking screw without a chisel end can be used.
  • the locking head of the locking screw is brought into proximity with the head of the bone screw to block its backward movement so that the implant 2400 remains anchored with the bone screw, i.e., so that the bone screw cannot back out of the bone.
  • the embedded locking screw also serves to prevent rotational displacement of implant 2400 , while blocking backward displacement of the first bone screw.
  • FIG. 34A depicts a posterior view of another embodiment 2500 of the implant of the invention.
  • Embodiment 2500 as well as all of the embodiments herein, can benefit from some or all of the features and advantages with regard to the other embodiments described herein.
  • embodiment 2500 has a natural or artificial facet joint spacer or inter-facet spacer 2510 that can have a tapered or thinned distal end 2512 .
  • the natural or artificial facet joint spacer or inter-facet spacer 2510 further can be curved so that a superior surface 2513 of the natural or artificial facet joint spacer or inter-facet spacer 2510 is convex, and an inferior surface 2515 is concave, to approximate the natural shape of the cervical facet joint that is to receive the implant 2500 .
  • the inferior surface 2515 is substantially flat whereby the superior surface 2513 is convex ( FIG. 34B ). As shown in FIG. 34B , the convex superior surface 2513 tapers downward at an increased angle toward the inferior surface 2515 at the distal end 2512 .
  • the natural or artificial facet joint spacer or inter-facet spacer 2510 also can be made of a flexible, biocompatible material, such as PEEK, to maintain joint mobility and flexibility.
  • the natural or artificial facet joint spacer or inter-facet spacer 2510 is connected flexibly with the lateral mass plate 2520 , preferably with a hinge 2522 .
  • the hinge 2522 allows the natural or artificial facet joint spacer or inter-facet spacer 2510 and the lateral mass plate 2520 of the implant 2500 to bend with respect to one another between an extended position and a bent or folded position as discussed above.
  • a first bone screw such as bone screw 1840 , can be inserted through a first bore 2530 through the lateral mass plate 2520 and embedded into the bone of the lateral mass of the cervical vertebra.
  • a second bone screw can be inserted through a second bore 2529 in the lateral mass plate 2520 , whereby the second bone screw would be embedded into the bone of the lateral mass of the cervical vertebra. Details of the first and second bores are discussed above.
  • the lateral mass plate 2520 is made of a biocompatible flexible material, preferably titanium or any other biocompatible flexible material as described herein, for example PEEK, that will support the use of bone screws and other hardware, as described below.
  • the lateral mass plate 2520 bends downward about the hinge 2522 over a wide range of angles relative to the natural or artificial facet joint spacer or inter-facet spacer 2510 .
  • any other type of interface between the natural or artificial facet joint spacer or inter-facet spacer 2510 and the lateral mass plate 2520 is contemplated (e.g. ball and socket joint). This flexibility facilitates positioning and insertion of the natural or artificial facet joint spacer or inter-facet spacer 2510 .
  • FIG. 34B depicts a side view of the natural or artificial facet joint spacer or inter-facet spacer and lateral mass plate in accordance with one embodiment.
  • the natural or artificial facet joint spacer or inter-facet spacer 2510 includes an hyper-extension tab 2522 in one embodiment.
  • the hyper-extension tab 2522 prevents the natural or artificial facet joint spacer or inter-facet spacer 2510 as well as the lateral mass plate 2520 from moving in a direction beyond the extended position which is shown in FIGS. 34A and 35B .
  • the lateral mass plate 2520 preferably includes a recess 2511 at the interface between the lateral mass plate 2520 and the natural or artificial facet joint spacer or inter-facet spacer 2510 which seats the tab 2522 in the extended position which is shown in FIG. 34A .
  • the natural or artificial facet joint spacer or inter-facet spacer 2510 is bent at an angle, the tab 2522 is not in contact with the recess 2511 . However, the tab 2522 comes into contact with the recess 2511 when in the extended position, as shown in FIG. 34A .
  • the tab 2522 when seated in the recess 2511 , prevents the natural or artificial facet joint spacer or inter-facet spacer 2510 and lateral mass plate 2520 from moving beyond the extended position.
  • This features aids in placing the implant into the facet joint as the implant is prevented from bending back beyond the extended position shown in FIG. 34B .
  • This arrangement allows the lateral mass plate 2520 to bend down to meet the spine when the natural or artificial facet joint spacer or inter-facet spacer 2510 is implanted in the facet joint.
  • the lateral mass plate 2520 preferably includes a third bore 2502 located near a rear edge, whereby the third bore 2052 preferably receives an engaging rod 2616 ( FIG. 35B ) of an implantation tool 2600 described below.
  • the third bore 2502 preferably extends through the superior and inferior surfaces of the lateral mass plate, although not necessarily.
  • the third bore 2502 is circular in shape, any other shape is contemplated which engages a correspondingly shaped engaging rod 2616 ( FIG. 35B ).
  • the rear edge 2504 of the lateral mass plate 2520 can be engaged by the engagement head 2606 ( FIG. 35B ) of the implantation tool 2600 as described below.
  • the lateral mass plate 2520 preferably includes one or more winged protrusions, such as tabs, wing lets or ears, 2508 which protrude from the side edges of the lateral mass plate 2520 .
  • FIG. 34A illustrates the implant 2500 having two winged protrusions 2508 .
  • the protrusions 2508 serve as guides to successfully couple the implant 2500 to the implantation tool 2600 .
  • the protrusions act as an engaging mechanism which secures the implant 2500 to the tool 2600 .
  • the winged protrusions 2508 are preferred and the implant 2500 can be configured in any other appropriate design to ensure that the implant 2500 is able to be effectively guided and secured to the implantation tool 2600 .
  • FIG. 35A depicts an implantation tool in accordance with one embodiment of the present invention.
  • the tool 2600 preferably includes a handle 2602 having a proximal end and a distal end.
  • the tool 2600 includes an actuating switch 2608 as well as a shaft 2604 extending from the distal end of the handle 2602 .
  • the shaft 2604 preferably extends axially with the handle 2602 , although the shaft 2604 may be at an angle with respect to the handle 2602 .
  • Extending from the shaft 2604 is an engagement head 2606 , whereby the engagement head is preferably oriented at an angle with respect to the shaft 2604 and/or the handle 2602 .
  • the angle of the head 2606 relative to the shaft 2604 aids the surgeon in the process of implanting the implant 2500 in the spine. This angle allows the surgeon to slip the natural or artificial facet joint spacer or inter-facet spacer 2510 into the facet joint with the tool 2600 preferably about a right angle to the spine. Preferably the head is at an angle between 45 and 90 degrees relative to the handle 2604 . However, other angles are contemplated.
  • the engagement head 2606 preferably has a forked configuration and includes a pair of side walls 2610 , an engagement seat 2612 as well as a receiving space 2618 which is defined as the area between the side walls 2610 and the seat 2612 .
  • the engagement head 2606 preferably includes a retractable engaging rod 2616 which extends partially into the receiving space 2618 .
  • the side walls 2610 each have an inner side which includes a slot 2612 whereby the slots 2612 face the receiving space 2618 .
  • the slots 2612 are dimensioned to slidably receive the wing protrusions 2508 of the lateral mass plate 2520 as well as secure the lateral mass plate 2520 to the engagement head 2606 .
  • the engagement seat 2612 receives the rear edge 2504 of the lateral mass plate 2520 .
  • the engagement head 2606 preferably includes the engaging rod 2616 , as shown in FIG. 35B .
  • the engaging rod 2616 is dimensioned to fit within the third bore 2502 in the lateral mass plate 2520 .
  • the engaging rod 2616 is coupled the switch 2608 on the handle 2602 , whereby actuation of the switch 2608 causes the engaging rod 2616 to retract.
  • the engaging rod 2616 Upon being retracted, the engaging rod 2616 disengages the third bore 2502 and allows the implant 2500 to be disengaged from the engagement head 2606 .
  • the tool 2600 includes a spring or other urging means to urge the engaging rod 2616 to the extended position, as shown in FIG. 35B .
  • the engaging rod 2616 is freely moveable between the extended and retracted positions without a biasing force applied thereto.
  • the engaging rod 2616 is shown as being a circular cylinder in FIGS. 35A and 35B .
  • the engaging rod 2616 can have any other shape which conforms to the shape of the third bore 2502 in the lateral mass plate 2520 .
  • the engagement head 2606 does not include an engaging rod 2616 but some other mechanism to secure the implant 2500 to the tool 2600 .
  • the slots 2612 in the side walls 2610 can be used to retain the implant 2500 in the head 2606 without the use of an engaging mechanism.
  • the implant 2600 is oriented to be right side up such that the rear surface 2504 of the implant 2500 will conform and mate with the engagement seat 2614 .
  • the implant 2500 is aligned with the forked portion of the engagement head 2606 , whereby the winged protrusions 2508 of the implant 2500 are inserted into the slot openings 2612 .
  • the lateral mass plate 2520 is guided into engagement by the slots 2612 until the rear edge 2504 mates with the engagement seat 2614 .
  • the engaging rod 2616 is then inserted into the third bore 2502 , thereby securing the lateral mass plate 2520 to the engagement head 2606 .
  • the user manually actuates the switch 2608 to retract the engaging rod 2616 to allow the lateral mass plate 2520 to be inserted completely in the receiving space.
  • the switch 2608 is then manually released when the bore 2502 and engaging rod 2616 are aligned such that the engaging rod 2616 then extends and engages the third bore 2502 .
  • contact between the superior surface of the lateral mass plate 2520 and the engaging rod 2616 causes the engaging rod 2616 to slightly retract while the plate 2520 is moved into the engagement seat 2614 .
  • the third bore 2502 preferably registers with the engaging rod 2616 , whereby the urging force causes the engaging rod 2616 to automatically engage the third bore 2502 .
  • the natural or artificial facet joint spacer or inter-facet spacer 2510 is inserted into the distracted facet joint as described in detail above.
  • the user preferably actuates the switch 2608 to disengage the engaging rod 2616 from the third bore 2502 .
  • the surgeon draws the tool 2600 away from the facet joint, whereby the lateral mass plate 2520 slides out of the received area and is guided by the slots 2612 .
  • the lateral mass plate 2520 is then anchored into the vertebral body as discussed above.

Abstract

Systems and method in accordance with the embodiments of the present invention can include an implant for positioning within a cervical facet joint for distracting the cervical spine, thereby increasing the area of the canals and openings through which the spinal cord and nerves must pass, and decreasing pressure on the spinal cord and/or nerve roots. The implant can be inserted laterally or posteriorly.

Description

    CLAIM OF PRIORITY
  • This application claims priority to United States Provisional Application No. 60/679,377, entitled INTER-CERVICAL FACET IMPLANTATION TOOL, filed May 10, 2005 [Our Reference No.: KLYC-01118US9], which application is incorporated herein by reference.
  • CROSS-REFERENCE TO RELATED APPLICATIONS
  • This application is related to the following applications: U.S. patent application Ser. No. 11/093,557, entitled INTER-CERVICAL FACET IMPLANT WITH LOCKING SCREW AND METHOD filed Mar. 30, 3005 [Our Reference No.: KLYC-01118US5], which claims priority to U. S. Provisional Application No. 60/635,453, entitled, INTER-CERVICAL FACET IMPLANT AND METHOD filed Dec. 13, 2004 [Our Reference No. KLYC-01118US0]; U.S. application Ser. No. 11/053,399, entitled INTER-CERVICAL FACET IMPLANT AND METHOD, filed Feb. 8, 2005 [Our Reference No. KLYC-01118US1]; U.S. application Ser. No. 11/053,624, entitled INTER-CERVICAL FACET IMPLANT AND METHOD, filed Feb. 8, 2005 [Our Reference No. KLYC-01118US2]; U.S. application Ser. No. 11/053,735, entitled INTER-CERVICAL FACET IMPLANT AND METHOD, filed Feb. 8, 2005 [Our Reference No. KLYC-01118US3]; U.S. application Ser. No. 11/053,346, entitled INTER-CERVICAL FACET IMPLANT AND METHOD, filed Feb. 8, 2005 [Our Reference No. KLYC-01122US0]; and U.S. application Ser. No. 11/093,689, entitled INTER-CERVICAL FACET IMPLANT AND METHOD FOR PRESERVING THE TISSUES SURROUNDING THE FACET JOINT, filed Mar. 30, 2005 [Our Reference No. KLYC-01124US0] each of which is incorporated herein in full, by reference.
  • TECHNICAL FIELD
  • This invention relates to interspinous process implants.
  • BACKGROUND OF THE INVENTION
  • The spinal column is a bio-mechanical structure composed primarily of ligaments, muscles, vertebrae and intervertebral disks. The bio-mechanical functions of the spine include: (1) support of the body, which involves the transfer of the weight and the bending movements of the head, trunk and arms to the pelvis and legs, (2) complex physiological motion between these parts, and (3) protection of the spinal cord and the nerve roots.
  • As the present society ages, it is anticipated that there will be an increase in adverse spinal conditions which are characteristic of older people. By way of example only, with aging comes an increase in spinal stenosis (including, but not limited to, central canal and lateral stenosis), and facet arthropathy. Spinal stenosis results in a reduction foraminal area (i.e., the available space for the passage of nerves and blood vessels) which compresses the cervical nerve roots and causes radicular pain. Humpreys, S. C. et al., Flexion and traction effect on C5-C6foraminal space, Arch. Phys. Med. Rehabil., vol. 79 at 1105 (September 1998). Another symptom of spinal stenosis is myelopathy, which results in neck pain and muscle weakness. Id. Extension and ipsilateral rotation of the neck further reduces the foraminal area and contributes to pain, nerve root compression, and neural injury. Id.; Yoo, J. U. et al., Effect of cervical spine motion on the neuroforaminal dimensions of human cervical spine, Spine, vol. 17 at 1131 (Nov. 10, 1992). In contrast, neck flexion increases the foraminal area. Humpreys, S. C. et al., supra, at 1105.
  • In particular, cervical radiculopathy secondary to disc herniation and cervical spondylotic foraminal stenosis typically affects patients in their fourth and fifth decade, and has an annual incidence rate of 83.2 per 100,000 people (based on 1994 information). Cervical radiculopathy is typically treated surgically with either an anterior cervical discectomy and fusion (“ACDF”) or posterior laminoforaminotomy (“PLD”), with or without facetectomy. ACDF is the most commonly performed surgical procedure for cervical radiculopathy, as it has been shown to increase significantly the foramina dimensions when compared to a PLF.
  • It is desirable to eliminate the need for major surgery for all individuals, and in particular, for the elderly. Accordingly, a need exists to develop spine implants that alleviate pain caused by spinal stenosis and other such conditions caused by damage to, or degeneration of, the cervical spine.
  • The present invention addresses this need with implants and methods for implanting an apparatus into at least one facet joint of the cervical spine to distract the cervical spine while preferably preserving mobility and normal lordotic curvature.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 shows a lateral view of two adjacent cervical vertebrae and spinous processes, highlighting the cervical facet joint.
  • FIG. 2 depicts a lateral view of the cervical spine with spinal stenosis.
  • FIG. 3A depicts correction of cervical stenosis or other ailment with a wedge-shaped embodiment of the implant of the invention positioned in the cervical facet joint.
  • FIG. 3B depicts correction of cervical kyphosis or loss of lordosis with a wedge-shaped embodiment of the invention with the wedge positioned in the opposite direction as that depicted in FIG. 3A.
  • FIG. 4 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention including a screw fixation device for attaching to a single vertebra.
  • FIG. 5 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising screw fixation of two implants, one implant fixed to each of two adjacent vertebrae.
  • FIG. 6 shows cervical spine kyphosis, or loss of lordosis.
  • FIG. 7 shows correction of cervical kyphosis, or loss of lordosis, with a further embodiment of the implant of the invention comprising two facet implants with screw fixation.
  • FIG. 8 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet implant and a keel.
  • FIG. 9 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising facet implant, a keel, and screw fixation.
  • FIG. 10 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet implant with teeth.
  • FIG. 11 depicts correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet implant with teeth and screw fixation.
  • FIG. 12 depicts correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants having bony in growth surfaces.
  • FIG. 13 depicts correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants having bony in growth surfaces and posterior alignment guide.
  • FIG. 14 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants with increased facet joint contact surfaces.
  • FIG. 15 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants having bony in growth surfaces and screw fixation.
  • FIG. 16 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet implants with articular inner surfaces.
  • FIG. 17 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet joint implant with a roller.
  • FIG. 18 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising a facet joint implant with a plurality of rollers.
  • FIG. 19 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet joint implants, screw fixation, and elastic restraint.
  • FIG. 20 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet joint implants, screw fixation, and spring restraint.
  • FIG. 21 shows correction of cervical stenosis or other ailment with a further embodiment of the implant of the invention, comprising two facet joint implants, screw fixation, and magnetic restraint.
  • FIG. 22A shows a perspective view of a further embodiment of implant of the invention.
  • FIG. 22B shows a perspective exploded view of the embodiment of the invention shown in FIG. 22A.
  • FIG. 23A depicts a posterior view of the embodiment of the implant of the invention shown in FIG. 22A.
  • FIG. 23B shows a posterior view of a locking plate of the embodiment of the implant of the invention shown in FIG. 22A.
  • FIG. 24A depicts a lateral side view of the embodiment of the implant of the invention shown in FIG. 22A.
  • FIG. 24B shows a lateral side view of the keel of the locking plate of the embodiment of the implant of the invention shown in FIG. 22A.
  • FIG. 25A shows a perspective view of a further embodiment of the implant of the invention.
  • FIG. 25B shows a side view of the embodiment of the implant of the invention in FIG. 25A, having a curved, uniformly-thick artificial facet joint spacer or inter-facet spacer including a tapered end
  • FIG. 26A shows a perspective view of a further embodiment of the implant of the invention.
  • FIG. 26B shows a posterior perspective view of the embodiment of the implant of the invention depicted in FIG. 26A.
  • FIG. 27A depicts a side view of the embodiment of the implant of the invention shown in FIGS. 26A and 26B.
  • FIG. 27B shows a posterior view of the embodiment of the implant of the invention shown in FIGS. 26A, 26B, and 27A, implanted in the cervical spine.
  • FIG. 28A depicts a posterior perspective view of a further embodiment of the implant of the invention.
  • FIG. 28B depicts a side view of the embodiment of the implant of the invention shown in FIG. 28A.
  • FIG. 29A depicts a side view of an embodiment of a sizing tool of the invention.
  • FIG. 29B depicts a top view of an embodiment of the sizing tool of the invention depicted in FIG. 29A.
  • FIG. 29C depicts a perspective view of an embodiment of the sizing tool of the invention depicted in FIGS. 29A-B.
  • FIG. 29D depicts a side view of the head of the sizing tool of the invention depicted in FIG. 29A
  • FIG. 29E depicts a cross-sectional view of the head of the sizing tool of the invention depicted in FIGS. 29A-C.
  • FIG. 30 is a flow diagram of an embodiment of a method of the invention.
  • FIG. 31A is posterior view of a further embodiment of the implant of the invention.
  • FIG. 31B is a side view of an embodiment of a locking screw of the implant of the invention depicted in FIG. 31A.
  • FIG. 32 is a posterior view of a further embodiment of the implant of the invention.
  • FIGS. 33A and 33B depict initial and final insertion positions of the embodiment of the invention depicted in FIG. 32.
  • FIG. 34A is a posterior view of a further embodiment of the implant of the invention.
  • FIG. 34B is a side view of a further embodiment of the implant of the invention.
  • FIG. 35A is a perspective view of an embodiment of the implantation tool of the invention.
  • FIG. 35B is a perspective view of the engagement head of the implantation tool of the invention.
  • DETAILED DESCRIPTION
  • Embodiments of the present invention provide for a minimally invasive surgical implantation method and apparatus for cervical spine implants that preserves the physiology of the spine. In particular, embodiments provide for distracting the cervical spine to increase the foraminal dimension in extension and neutral positions. Such implants, when implanted in the cervical facet joints, distract, or increase the space between, the vertebrae to increase the foraminal area or dimension, and reduce pressure on the nerves and blood vessels of the cervical spine.
  • The facet joints in the spine are formed between two vertebrae as follows. Each vertebra has four posterior articulating surfaces: two superior facets and two inferior facets, with a superior facet from a lower vertebra and an inferior facet of an upper vertebra forming a facet joint on each lateral side of the spine. In the cervical spine, the upward inclination of the superior articular surfaces of the facet joints allows for considerable flexion and extension, as well as for lateral mobility. Each facet joint is covered by a dense, elastic articular capsule, which is attached just beyond the margins of the articular facets. The capsule is larger and looser in the cervical spine than in the thoracic and lumbar spine. The inside of the capsule is lined by a synovial membrane which secretes synovial fluid for lubricating the facet joint. The exterior of the joint capsule is surrounded by a capsular ligament. It is this ligament and the joint capsule that must be cut in the embodiments of the method described herein for inserting the artificial facet joint.
  • In a specific preferred embodiment, an implanted interfacet spacer of 1.5 mm to 2.5 mm in width can result in interfacet distraction that increases foraminal dimension in extension and neutral. Other interfacet spacer dimensions also are contemplated by the invention described herein below. The present embodiments also preserve mobility of the facet joints.
  • Further embodiments of the present invention accommodate the distinct anatomical structures of the spine, minimize further trauma to the spine, and obviate the need for invasive methods of surgical implantation. Embodiments of the present invention also address spinal conditions that are exacerbated by spinal extension.
  • FIG. 1 shows a simplified diagram of a portion of the cervical spine, focusing on a cervical facet joint 1 formed between two adjacent cervical vertebrae. The spinous processes 3 are located posteriorly and the vertebral bodies 5 are located anteriorly, and a nerve root canal 7 is visible. Each vertebra has four posterior articulating surfaces: two superior facets and two inferior facets, with a superior facet from a lower vertebra and an inferior facet of an upper vertebra forming a facet joint on each lateral side of the spine. In the cervical spine, the upward inclination of the superior articular surfaces of the facet joints allows for considerable flexion and extension, as well as for lateral mobility. Each facet joint is covered by a dense, elastic articular capsule, which is attached just beyond the margins of the articular facets. The capsule is large and looser in the cervical spine than in the thoracic and lumbar spine. The inside of the capsule is lined by a synovial membrane which secretes synovial fluid for lubricating the facet joint. The exterior of the joint capsule is surrounded by a capsular ligament. It is this ligament that may be pushed out of the way in the embodiments of the method for inserting the artificial facet joint, described herein.
  • FIG. 2 depicts cervical foraminal stenosis. From the drawing, the nerve root canal 7 is narrowed relative to the nerve root canal 7 depicted in FIG. 1. The spinal canal and/or intervertebral foramina also can be narrowed by stenosis. The narrowing can cause compression of the spinal cord and nerve roots.
  • FIG. 3A shows a first embodiment 100 of the present invention, which is meant to distract at least one facet joint, in order to increase the dimension of the neural foramen while retaining facet joint mobility. The wedge-shaped embodiment or inter-facet spacer 100 is a wedge-shaped implant that can be positioned in the cervical facet joint 101 to distract the joint and reverse narrowing of the nerve root canal 107. In this embodiment or inter-facet spacer 100, the implant is positioned with the narrow portion of the wedge facing anteriorly. However, it is also within the scope of the present invention to position embodiment or inter-facet spacer 100 (FIG. 3B) with the wide portion of the wedge facing anteriorly, to correct for cervical kyphosis or loss of cervical lordosis.
  • It is to be understood that implants in accordance with the present invention, and/or portions thereof can be fabricated from somewhat flexible and/or deflectable material. In these embodiments, the implant and/or portions thereof can be made out of a polymer, such as a thermoplastic. For example, in one embodiment, the implant can be made from polyketone, known as polyetheretherketone (“PEEK”). Still more specifically, the implant can be made from PEEK 450G, which is an unfilled PEEK approved for medical implantation available from Victrex of Lancashire, Great Britain. Other sources of this material include Gharda located in Panoli, India. PEEK has the following approximate properties:
    Property Value
    Density 1.3 g/cc
    Rockwell M 99
    Rockwell R 126
    Tensile Strength 97 MPa
    Modulus of Elasticity 3.5 GPa
    Flexural Modulus 4.1 GPa
  • The material specified has appropriate physical and mechanical properties and is suitable for carrying and spreading a physical load between the adjacent spinous processes. The implant and/or portions thereof can be formed by extrusion, injection, compression molding and/or machining techniques.
  • In some embodiments, the implant can comprise, at least in part, titanium or stainless steel, or other suitable implant material which is radiopaque, and at least in part a radiolucent material that does not show up under x-ray or other type of imaging. The physician can have a less obstructed view of the spine under imaging, than with an implant comprising radiopaque materials entirely. However, the implant need not comprise any radiolucent materials.
  • It should be noted that the material selected also can be filled. For example, other grades of PEEK are also available and contemplated, such as 30% glass-filled or 30% carbon-filled, provided such materials are cleared for use in implantable devices by the FDA, or other regulatory body. Glass-filled PEEK reduces the expansion rate and increases the flexural modulus of PEEK relative to that unfilled PEEK. The resulting product is known to be ideal for improved strength, stifffiess, or stability. Carbon-filled PEEK is known to enhance the compressive strength and stiffness of PEEK and to decrease its expansion rate. Carbon-filled PEEK offers wear resistance and load-carrying capability.
  • In this embodiment or inter-facet spacer 100, the implant is manufactured from PEEK, available from Victrex. As will be appreciated, other suitable similarly biocompatible thermoplastic or thermoplastic polycondensate materials that resist fatigue, have good memory, are flexible, and/or deflectable, have very low moisture absorption, and good wear and/or abrasion resistance, can be used without departing from the scope of the invention. The spacer also can be comprised of polyetherketoneketone (“PEKK”). Other material that can be used include polyetherketone (“PEK”), polyetherketoneetherketoneketone (“PEKEKK”), and polyetheretherketoneketone (“PEEKK”), and generally a polyaryletheretherketone. Further, other polyketones can be used as well as other thermoplastics. Reference to appropriate polymers that can be used in the implant can be made to the following documents, all of which are incorporated herein by reference. These documents include: PCT Publication WO 02/02158 A1, dated Jan. 10, 2002, entitled “Bio-Compatible Polymeric Materials”; PCT Publication WO 02/00275 A1, dated Jan. 3, 2002, entitled “Bio-Compatible Polymeric Materials; and, PCT Publication WO 02/00270 A1, dated Jan. 3, 2002, entitled “Bio-Compatible Polymeric Materials.” Other materials such as Bionate®, polycarbonate urethane, available from the Polymer Technology Group, Berkeley, Calif., may also be appropriate because of the good oxidative stability, biocompatibility, mechanical strength and abrasion resistance. Other thermoplastic materials and other high molecular weight polymers can be used.
  • Turning now to FIG. 4, the embodiment 200 of the implant has a joint insert or inter-facet spacer 210, also herein referred to as an artificial facet joint or inter-facet spacer, that is positioned in the cervical facet joint 101. The joint insert or inter-facet spacer 210 can be wedge-shaped with the narrow part of the wedge facing anteriorly. Alternatively, the joint insert or inter-facet spacer 210 need not be wedge-shaped but can be of substantially uniform thickness, the thickness determined by an individual patient's need for distraction of the cervical facet joint 201. As with embodiment 100, one objective of this embodiment is facet joint distraction, and joint mobility after implantation. The joint insert 210 is continuous with a posterior sheath 220 bent at an angle from the joint insert or inter-facet spacer 210 to align substantially parallel with the bone. The posterior sheath can lie against the lamina, preferably against the lateral mass. The posterior sheath 220 can have a bore 230 which can accept a bone screw 240. Alternatively, the bore 230 can accept any other appropriate and/or equivalent fixation device capable of fixing the embodiment 200 to the spine. The device is thereby affixed to the vertebra, preferably by fixing to the lateral mass.
  • FIG. 5 shows embodiment 300, which is the use of two embodiments 200, each fixed to one of two adjacent cervical vertebrae. As with embodiment 200, the implanted facet joint is distracted and joint mobility is retained. A joint insert or inter-facet spacer 310 from each of the two implants is inserted and positioned in the cervical facet joint 301. In this embodiment, the joint inserts 310 are substantially flat and parallel to each other and are not wedge-shaped. Alternatively, the joint inserts or inter-facet spacers 310 can together define a wedge-shaped insert that is appropriate for the patient. The two joint inserts or inter-facet spacers 310 combined can have, by way of example, the shape of the joint insert or inter-facet spacers 210 in FIG. 4. Embodiment 300 then can be fixed to the spine with a screw 340 or any other appropriate fixation device, inserted through a bore 330 in the posterior sheath 320. The posterior sheath 320 can be threaded to accept a screw. The screw can be embedded in the lamina, preferably in the lateral mass, where possible.
  • It is within the scope of the present invention to use and/or modify the implants of the invention to correct cervical spine kyphosis, or loss of lordosis. FIG. 6 depicts a cervical spine lordosis. FIG. 7 demonstrates an embodiment 400 which contemplates positioning two implants to correct for this spinal abnormality while retaining facet joint mobility. The joint insert or inter-facet spacer 410 of each implant is shaped so that it is thicker at its anterior portion. Alternatively, the implants can be shaped to be thicker at the posterior ends, for example as depicted in FIG. 3A. The posterior sheath 420 of each implant is bent at an angle from the joint insert or inter-facet spacer 410 to be positioned adjacent to the lateral mass and/or lamina, and has a bore 430 to accept a screw 440 or other appropriate and/or equivalent fixation means to fix the embodiment 400 to the spine, preferably to the lateral mass. The placement of two joint inserts or inter-facet spacers 410 in the cervical facet joint 401 distracts the facet joint, which shifts and maintains the vertebrae into a more anatomical position to preserve the physiology of the spine.
  • FIG. 8 shows a further embodiment 500 of the implant of the invention, wherein the joint insert or inter-facet spacer 510 has a keel 550 on an underside of the joint insert or inter-facet spacer 510. The keel 550 can be made of the same material or materials set forth above. The surfaces of the keel 550 can be roughened in order to promote bone in growth to stabilize and fix the implant 500. In other embodiments, the keel 550 can be coated with materials that promote bone growth such as, for example, bone morphogenic protein (“BMP”), or structural materials such as hyaluronic acid “HA,” or other substances which promote growth of bone relative to and into the keel 550.
  • The keel 550 can be embedded in the facet bone, to facilitate implant retention. The keel 550 can be placed into a channel in the facet bone. The channel can be pre-cut. Teeth (not shown), preferably positioned posteriorly, also may be formed on the keel 550 for facilitating retention of the implant 500 in the cervical facet joint 501. As noted above, the joint insert or inter-facet spacer 510 can be substantially flat or wedge-shaped, depending upon the type of distraction needed, i.e., whether distraction is also necessary to correct abnormal curvature or lack of curvature in the cervical spine. Because the joint is not fused, mobility is retained, as with the embodiments described above and herein below.
  • FIG. 9 illustrates that a further embodiment 600 of the implant of the invention can have both screw fixation and a keel 650 for stability and retention of the implant 600. On embodiment 600, the joint insert or inter-facet spacer 610 is continuous with a posterior sheath 620 having a bore hole 630 to accept a screw 640 which passes through the bore 630 and into the bone of the vertebrae, preferably into the lateral mass, or the lamina. The bore 630 can be threaded or not threaded where it is to accept a threaded screw or equivalent device. Alternatively, the bore 630 need not be threaded to accept a non-threaded equivalent device. The keel 650 is connected with the joint insert or inter-facet spacer 610 and embeds in the bone of the cervical facet joint 601 to promote implant retention.
  • A further alternative embodiment 700 is illustrated in FIG. 10. In this embodiment 700, the joint insert 710 has on a lower side at least one tooth 760. It should be clear to one of ordinary skill in the art that a plurality of teeth 760 is preferable. The teeth 760 are able to embed in the bone of the cervical facet joint 701 to facilitate retention of the implant 700 in the joint 701. The teeth 760 can face in a direction substantially opposite the direction of insertion, for retention of the implant 700. As above, the joint insert or inter-facet spacer 710 can be wedge-shaped or substantially even in thickness, depending upon the desired distraction. Because the implant distracts and is retained without fusion, facet joint mobility is retained.
  • FIG. 11 depicts a further embodiment 800 of the implant of the invention. In this embodiment 800, the joint insert or inter-facet spacer 810 is continuous with a posterior sheath 820 having a bore 830 for accepting a fixation device 840, as described above. The fixation device 840 can be a screw which fits into a threaded bore 830; alternatively, the fixation device 830 can be any other compatible and appropriate device. This embodiment 800 further combines at least one tooth 860 on an underside of the joint insert or inter-facet spacer 810 with the posterior sheath 820, bore 830 and fixation device 840 to address fixation of the implant 800 in a cervical facet joint 801. It will be recognized by one of ordinary skill in the art that the implant 800 can have a plurality of teeth 860 on the underside of the joint insert or inter-facet spacer 810.
  • FIG. 12 shows yet another embodiment 900 of an implant of the present invention. In this embodiment 900, the joint inserts or inter-facet spacers 910 of two implants 900 are positioned in a cervical facet joint 901. As described above, the joint inserts or inter-facet spacers 910 can be wedge-shaped as needed to restore anatomical curvature of the cervical spine and to distract, or the joint inserts or inter-facet spacers 910 can be of substantially uniform thickness. The implants 900 each comprise a joint insert or inter-facet spacer 910 with an outer surface 970 that interacts with the bone of the cervical facet joint 901. On the upper implant 900, the surface 970 that interacts with the bone is the upper surface 970 and on the lower implant 900, the surface 970 that interacts with the bone is the lower surface 970. Each surface 970 can comprise a bone in growth surface 980 to create a porous surface and thereby promote bone in growth and fixation. One such treatment can be with plasma spray titanium, and another, with a coating of sintered beads. Alternatively, the implant 900 can have casted porous surfaces 970, where the porous surface is integral to the implant 900. As a further alternative, the surfaces 970 can be roughened in order to promote bone in growth into these defined surfaces of the implants 900. In other embodiments, the surfaces 970 can be coated with materials that promote bone growth such as for example bone morphogenic protein (“BMP”), or structural materials such as hyaluronic acid (“HA”), or other substances which promote growth of bone on other external surfaces 970 of the implant 900. These measures facilitate fixation of the implants 900 in the facet joint, but do not result in fusion of the joint, thereby retaining facet joint mobility, while also accomplishing distraction of the joint.
  • FIG. 13 depicts yet another embodiment 1000 of the implant of the present invention. In this embodiment 1000, the joint inserts or inter-facet spacers 1010 of two implants 1000 are positioned in a cervical facet joint 1001. As described above, the joint inserts or inter-facet spacers 1010 can be wedge-shaped as needed to restore anatomical curvature of the cervical spine and to distract, or the joint inserts or inter-facet spacers 1010 can be of substantially uniform thickness. The implants 1000 each comprise a joint insert or inter-facet spacer 1010 with an outer surface 1070 that interacts with the bone of the cervical facet joint 1001. On the upper implant 1000, the surface 1070 that interacts with the bone is the upper surface and on the lower implant 1000, the surface 1070 that interacts with the bone is the lower surface. As set forth above, each outer surface 1070 can comprise a bone in growth surface 1080 to create a porous surface and thereby promote bone in growth and fixation, without facet joint fusion and loss of mobility. In one preferred embodiment, the bone in growth surface 1080 can be created with plasma spray titanium, and/or with a coating of sintered beads. In an alternative preferred embodiment, the implant 1000 can have casted porous surfaces 1070, where the porous surface is integral to the implant 1000. In a further alternative preferred embodiment, the surfaces 1070 can be roughened in order to promote bone in growth into these defined surfaces of the implants 1000. In other preferred embodiments, the surfaces 1070 can be coated with materials that promote bone growth such as for example BMP, or structural materials such as HA, or other substances which promote growth of bone on other external surfaces 1070 of the implant 1000.
  • The implant 1000 can have a posterior alignment guide 1090. The posterior alignment guides 1090 of each implant 1000 can be continuous with the joint inserts or inter-facet spacers 1010. The posterior alignment guides substantially conform to the bone of the vertebrae when the joint inserts or inter-facet spacers 1010 are inserted into the cervical facet joint 1001. The posterior alignment guides 1090 are used to align the implants 1000 so that the joint inserts 1010 contact each other and not the bones of the cervical facet joint 1001 when the joint inserts 1010 or inter-facet spacers are positioned in the cervical facet joint 1001.
  • FIG. 14 depicts a further embodiment 1100 of the implant of the present invention. In this embodiment 1100, the joint inserts 1110 of two implants 1100 are inserted into the cervical facet joint 1101. Each of the joint inserts or inter-facet spacers 1110 is continuous with a cervical facet joint extender or facet-extending surface 1192. The bone contacting surfaces 1170 of the joint inserts or inter-facet spacers 1110 are continuous with, and at an angle to, the bone contacting surfaces 1193 of the cervical facet joint extenders 1192, so that the cervical facet joint extenders 1192 conform to the bones of the vertebrae exterior to the cervical facet joint 1101. The conformity of the cervical facet joint extenders 1192 is achieved for example by forming the cervical facet joint extenders 1192 so that when the join inserts or inter-facet spacers 1110 are positioned, the cervical facet joint extenders 1192 curve around the bone outsider the cervical facet joint 1101.
  • The cervical facet joint extenders have a second surface 1184 that is continuous with the joint articular surfaces 1182 of the joint inserts or inter-facet spacers 1110. The second surfaces 1184 extend the implant 1100 posteriorly to expand the joint articular surfaces 1182 and thereby to increase contact and stability of the spine at least in the region of the implants 1100. It is to be understood that such facet joint extenders 1192 can be added to the other embodiments of the invention described and depicted herein.
  • The embodiment depicted in FIG. 15 shows two implants 1200 positioned in a cervical facet joint 1201, having bony in growth surfaces as one preferred method of fixation, and using screws as another preferred method of fixation. In this embodiment, each of two implants 1200 has a joint insert or inter-facet spacer 1210 positioned in a cervical facet joint 1201. As described above, the joint inserts or inter-facet spacers 1210 can be wedge-shaped as needed to restore anatomical curvature of the cervical spine and to distract, or the joint inserts or inter-facet spacers 1210 can be of substantially uniform thickness. The implants 1200 each comprise a joint insert 1210 with an outer surface 1270 that interacts with the bone of the cervical facet joint 1001. On the upper implant 1200, the surface 1270 that interacts with the bone is the upper surface and on the lower implant 1200, the surface 1270 that interacts with the bone is the lower surface. As set forth above, each outer surface 1270 can comprise a bone in growth surface 1280 to create a porous surface and thereby promote bone in growth and fixation. In one preferred embodiment, the bone in growth surface 1280 can be created with plasma spray titanium, and/or with a coating of sintered beads. In an alternative preferred embodiment, the implant 1200 can have casted porous surfaces 1270, where the porous surface is integral to the implant 1200. In a further alternative embodiment, the surfaces 1270 can be roughened in order to promote bone in growth into these defined surfaces of the implants 1200. In other preferred embodiments, the surfaces 1270 can be coated with materials that promote bone growth such as for example BMP, or structural materials such as HA, or other substances which promote growth of bone on other external surfaces 1270 of the implant 1200.
  • Screw fixation or other appropriate fixation also can be used with implants 1200 for fixation in the cervical facet joint 1201. The joint insert or inter-facet spacer 1210 is continuous with a posterior sheath 1220 bent at an angle from the joint insert or inter-facet spacer 1210 to align substantially parallel with the bone, preferably the lateral mass or lamina. The posterior sheath 1220 can have a bore 1230 which can accept a bone screw 1240, preferably into the lateral mass or lamina. Alternatively, the bore 1230 can accept any other appropriate and/or equivalent fixation means for fixing the embodiment 1200 to the spine.
  • FIG. 16 depicts a further preferred embodiment of the present invention. In this embodiment 1300, two joint inserts or inter-facet spacers 1310 are positioned in the cervical facet joint 1301. The joint inserts each have outer surfaces 1370 that interact with the bone of the vertebrae forming the cervical facet joint. These outer surfaces 1370 of the embodiment 1300 can be treated to become bone in growth surfaces 1380, which bone ingrowth surfaces 1380 contribute to stabilizing the two joint inserts or inter-facet spacers 1310 of the implant 1300. In one preferred embodiment, the bone ingrowth surface 1380 can be created with plasma spray titanium, and/or with a coating of sintered beads. In an alternative preferred embodiment, the implant 1300 can have casted porous surfaces 1370, where the porous surface is integral to the implant 1300. In a further alternative embodiment, the surfaces 1370 can be roughened in order to promote bone ingrowth into these defined surfaces of the implants 1300. In other preferred embodiments, the surfaces 1370 can be coated with materials that promote bone growth such as for example BMP, or structural materials such as HA, or other substances which promote growth of bone on other external surfaces 1370 of the implant 1300. This fixation stabilizes the implant 1300 in the facet joint without fusing the joint, and thus the implant preserves joint mobility, while accomplishing distraction and increasing foraminal dimension.
  • Also shown in FIG. 16 are articular inner surfaces 1382 of the implants 1300. These surfaces can be formed from a metal and polyethylene, the material allowing flexibility and providing for forward bending/flexion and backward extension of the cervical spine. The embodiment 1300 of FIG. 16 can be made in at least two configurations. The first configuration includes a flexible spacer 1382 made, by way of example, using polyethylene or other suitable, flexible implant material. The flexible spacer 1382 can be permanently affixed to the upper and lower joint insert or inter-facet spacer 1310. The spacer 1382 can be flat or wedge-shaped or have any other shape that would correct the curvature of the spine. In other configurations, the spacer 1382 can be affixed to only the upper insert or inter-facet spacer 1310 or to only the lower insert 1310. Alternatively, a spacer 1382 can be affixed to each of an upper insert or inter-facet spacer 1310 and a lower insert or inter-facet spacer 1310 with the upper insert or inter-facet spacer 1310 and the lower insert or inter-facet spacer 1310 being separate units.
  • FIG. 17 shows a further preferred embodiment of the implant of the present invention. In this embodiment 1400, the implant has a roller 1496 mounted on a joint insert or inter-facet spacer 1410, the roller being a further means of preserving joint mobility while accomplishing distraction. Both the roller 1496 and the joint insert or inter-facet spacer 1410 are positioned in the cervical facet joint 1401. The joint insert or inter-facet spacer 1410 as in other embodiments has a bone-facing surface 1470 and joint articular surface 1482. The bone-facing surface 1470 can interact with the lower bone of the cervical facet joint 1401. Alternatively, the bone-facing surface can interact with the upper bone of the cervical facet joint 1401. Between the bone-facing surface 1470 and the joint articular surface 1482 is an axis about which the roller 1496 can rotate. The roller 1496 rotates in a cavity in the joint insert 1410, and interacts with the top bone of the cervical facet joint 1401. Alternatively, where the bone-facing surface 1470 of the joint insert or inter-facet spacer 1410 interacts with the top bone of the cervical facet joint 1401, the roller 1496 rotates in a cavity in the joint insert or inter-facet spacer 1410 and interacts with the lower bone of the cervical facet joint 1401. The rotation of the roller 1496 allows flexion and extension of the cervical spine. Alternatively, a roller such as roller 1496 can be secured to an upper and a lower insert such as inserts 410 in FIG. 7. As depicted in FIG. 18, a plurality of rollers 1496 also is possible.
  • FIG. 19 depicts a further embodiment of the implant of the present invention. In this embodiment, two implants 1500 are implanted in the cervical facet joint 1501. Screw fixation or other appropriate fixation is used with implants 1500 for fixation in the cervical facet joint 1501. The joint insert or inter-facet spacer 1510 is continuous with a posterior sheath 1520 bent at an angle from the joint insert or inter-facet spacer 1510 to align substantially parallel with the bone, preferably the lateral mass or lamina. The posterior sheath 1520 of each implant 1500 can have a bore 1530 which can accept a bone screw 1540, preferably into the lateral mass or lamina. Alternatively, the bore 1530 can accept any other appropriate and/or equivalent fixation means for fixing the embodiment 1500 to the spine. The head of the screw 1540 in each posterior sheath 1520 of each implant 1500 has a groove 1598 or other mechanism for retaining an elastic band 1597. The elastic band 1597 is looped around each of the two screws 1540 to restrain movement of the cervical spine without eliminating facet joint mobility. The band 1597 preferably can restrain flexion and lateral movement. The elastic band 1597 can be made of a biocompatible, flexible material.
  • FIG. 20 shows an alternative to use of an elastic band as in FIG. 19. In the embodiment in FIG. 20, the elastic band is replaced with a spring restraint 1699, which extends between the heads of two screws 1640, one screw fixing each of two implants 1600 in the cervical facet joint 1601.
  • FIG. 21 shows another alternative to using an elastic band and/or a spring as in FIGS. 19 or 20. In FIG. 21, magnets 1795 are used for restraint between the two screws 1740. The magnet 1795 can either be comprised of two opposing magnetic fields or two of the same magnetic fields to operate to restrain movement. The head of one of the two screws 1740 is magnetized, and the head of the other screw 1740 is magnetized with either the same or opposite field. If the magnets 1795 have the same polarity, the magnets 1795 repel each other and thus limit extension. If the magnets 1795 have opposite polarities, the magnets 1795 attract each other and thus limit flexion and lateral movement.
  • FIGS. 22A-24B, depict a further embodiment 1800 of the implant of the present invention. In this embodiment, a facet joint spacer (or insert) or inter-facet spacer (or insert)1810 is connected with a lateral mass plate (also referred to as an anchoring palte) 1820 with a hinge 1822. The hinge 1822 allows the lateral mass plate 1820 to bend at a wide range of angles relative to the artificial facet joint and preferably at an angle of more than 90 degrees, and this flexibility facilitates positioning and insertion of the facet joint spacer (or insert) or inter-facet spacer (or insert)1810 into a patient's facet joint, the anatomy of which can be highly variable among individuals. This characteristic also applies to embodiments described below, which have a hinge or which are otherwise enabled to bend by some equivalent structure or material property. The hinge 1822 further facilitates customizing the anchoring of the implant, i.e., the positioning of a fixation device. The hinge enables positioning of the lateral mass plate 1820 to conform to a patient's cervical spinal anatomy, and the lateral mass plate 1820 accepts a fixation device to penetrate the bone. The facet joint spacer (or insert) or inter-facet spacer (or insert)1810 can be curved or rounded at a distal end 1812 (FIG. 23A), and convex or dome-shaped on a superior surface 1813 to approximate the shape of the bone inside the facet joint. The inferior surface 1815 can be flat or planar. Alternatively, the inferior surface 1815 can be concave. As another alternative, the inferior surface 1815 can be convex.
  • The lateral mass plate 1820, when implanted in the spine, is positioned outside the facet joint, preferably against the lateral mass or against the lamina. The lateral mass plate 1820 has a bore 1830 therethrough. The bore 1830 can accept a bone screw 1840, also referred to as a lateral mass screw, to secure the lateral mass plate 1820 preferably to the lateral mass or alternatively to another part of the spine, and thus to anchor the implant. The lateral mass screw 1840 preferably has a hexagonal head to accept an appropriately-shaped wrench. As described below, the head accepts a compatible probe 1826 from a locking plate 1824.
  • The locking plate 1824 includes a keel 1828 with a wedge shaped distal end to anchor the implant, preferably in the lateral mass or in the lamina, outside the facet joint and to prevent rotation of the lateral mass plate 1820 and the locking plate 1824. The keel 1828 aligns with a groove 1823 through an edge of the lateral mass plate 1820 to guide and align the keel 1828 as the keel 1828 cuts into a vertebra.
  • As noted above, the locking plate 1824 includes a probe 1826 that fits against the head of the lateral mass screw 1840. The locking plate further includes a bore 1831 that can accept a machine screw (not shown) which passes through to an aligned bore 1829 in the lateral mass plate 1820 to hold the locking plate 1824 and the lateral mass plate 1820 together without rotational displacement relative to each other. The locking plate 1824 thus serves at least two functions: (1) maintaining the position of the lateral mass screw 1840 with the probe 1826, so that the screw 1840 does not back out; and (2) preventing rotation of the implant with the keel 1828 and machine screw relative to the cervical vertebra or other vertebrae.
  • It is to be understood that other mechanisms can be used to lock the locking plate 1824 to the lateral mass plate 1820. For example, the locking plate can include a probe with barbs that can be inserted into a port in the lateral mass plate. The barbs can become engaged in ribs that define the side walls of the port in the lateral mass plate.
  • In the preferred embodiment depicted in FIGS. 25A, 25B, the lateral mass plate 1920 includes a recessed area 1922 for receiving the locking plate 1924 so that the locking plate 1924 is flush with the upper surface 1925 of the lateral mass plate 1920 when the probe 1926 is urged against the lateral mass screw 1940 and the keel 1928 is inserted into the lateral mass or the lamina of the vertebra. In the preferred embodiment depicted in FIGS. 25A, 25B, the shape and contours of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 can facilitate insertion of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 into the cervical facet joint. In this embodiment, the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 has a rounded distal end 1912. The distal end 1912 is tapered in thickness to facilitate insertion. The tapered distal end 1912 meets and is continuous with a proximal mid-section 1916 which, in this preferred embodiment, has a uniform thickness, and is connected flexibly, preferably with a hinge 1922, to the lateral mass plate 1920, as described above. The facet joint spacer (or insert) or inter-facet spacer (or insert) 1910, with its proximal mid-section 1916 and tapered distal end 1912, is curved downward, causing a superior surface 1913 of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 to be curved. The curve can cause the superior surface 1913 to be convex, and the convexity can vary among different implants 1900 to suit the anatomical structure of the cervical facet joint(s) of a patient. An inferior surface 1915 accordingly can be preferably concave, flat, or convex. The curved shape of the implant can fit the shape of a cervical facet joint, which is comprised of an inferior facet of an upper vertebra and a superior facet of a lower adjacent vertebra. The convex shape of the superior surface 1913 of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 fits with a concave shape of the inferior facet of the upper cervical vertebrae. The concave shape of the inferior surface 1915 of the facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 fits with the convex shape of the superior facet of the cervical vertebrae. The degree of convexity and concavity of the facet joint spacer (or insert) or inter-facet spacer (or insert) inferior and superior surfaces can be varied to fit a patient's anatomy and the particular pairing of adjacent cervical vertebrae to be treated. For example, a less-curved facet joint spacer (or insert) or inter-facet spacer (or insert) 1910 can be used where the patient's cervical spinal anatomy is sized (as described below) and found to have less convexity and concavity of the articular facets. Generally for the same level the input for the right and left facet joint will be similarly shaped. It is expected that the similarity of shape of the facet joint spacer (or insert) or inter-facet spacer (or insert) and the smooth, flush surfaces will allow distraction of the facet joint without loss of mobility or damage to the bones of the cervical spine. Further, and preferably, the width of the mid-section 1916 is from 1.5 mm to 2.5 mm.
  • Except as otherwise noted above, the embodiment shown in FIGS. 22A-24B is similar to the embodiment shown in FIGS. 25A, 25B. Accordingly the remaining elements on the 1900 series of element numbers is preferably substantially similar to the described elements in the 1800 series of element numbers, as set forth above. Thus, by way of example, elements 1923, 1928, 1929 and 1930 are similar, respective elements 1823, 1828, 1829 and 1830.
  • FIG. 30 is a flow chart of the method of insertion of an implant of the invention. The embodiment 1800 or 1900 of the present invention preferably is inserted in the following manner (only elements of the embodiment 1800 will be set forth herein, for purposes of the written description of a method of the invention). First the facet joint is accessed. A sizing tool 2200 (see FIGS. 29A-C) can be inserted to select the appropriate size of an implant of the invention for positioning in the cervical facet joint. This step may be repeated as necessary with, if desired, different sizes of the tool 2200 until the appropriate size is determined. This sizing step also distracts the facet joint and surrounding tissue in order to facilitate insertion of the implant. Then, the natural or artificial facet joint spacer or inter-facet spacer 1810 is urged between the facets into the facet joint. The facet itself is somewhat shaped like a ball and socket joint. Accordingly, in order to accommodate this shape, the natural or artificial joint spacer or inter-facet spacer 1810 can have a rounded leading edge shaped like a wedge or tissue expander to cause distraction of the facet joint as the natural or natural or artificial facet joint spacer or inter-facet spacer spacer or inter-facet spacer is urged into the facet joint of the spine. The natural or artificial facet joint spacer or inter-facet spacer 1810 also includes the convex surface 1813 in order to more fully accommodate the shape of the facet joint of the spine. However, as set forth above and as depicted in FIG. 25B, it is possible in the alternative to have a curve-shaped natural or artificial facet joint spacer or inter-facet spacer 1910 with a convex superior surface 1913 and a concave inferior surface 1915, the distal end 1912 tapering to facilitate insertion, while the remainder of the natural or artificial facet joint spacer or inter-facet spacer 1910, (i.e., the proximal section 1916) has a uniform thickness.
  • Once the natural or artificial joint spacer or inter-facet spacer 1810 is positioned, the lateral mass plate 1820 is pivoted downward about the hinge 1822 adjacent to the vertebrae and preferably to the lateral mass or to the lamina. Thus the lateral mass plate 1820 may be disposed at an angle relative to the natural or artificial facet joint spacer or inter-facet spacer 1810 for a representative spine configuration. It is to be understood that as this embodiment is hinged the final position of the lateral mass plate 1820 relative to the natural or artificial facet joint spacer or inter-facet spacer 1810 will depend on the actual spine configuration. It is to be understood that embodiments of the invention can be made without a hinge, as long as the connection between the natural or artificial facet joint spacer or inter-facet spacer and the lateral mass plate is flexible enough to allow the lateral mass plate to be bent relative to the natural or artificial facet joint spacer or inter-facet spacer in order to fit the anatomy of the patient. Once the lateral mass plate 1820 is positioned, or prior to the positioning of the lateral mass plate 1820, a bore can be drilled in the bone to accommodate the bone screw 1824. Alternatively the screw 1824 can be self-tapping. The screw is then placed through the bore 1830 and secured to the bone, preferably the lateral mass or the lamina, thereby holding the natural or artificial facet joint spacer or inter-facet spacer 1810 in place. In order to lock the bone screw 1824 in place and to lock the position of the natural or artificial facet joint spacer or inter-facet spacer 1810 and the lateral mass plate 1820 in place, the locking plate 1824 is positioned over the lateral mass plate 1820. So positioned, the probe 1826 is positioned through the bore 1830 and against the head of the bone screw to keep the bone screw from moving. The keel 1828, having a sharp chisel-shaped end, preferably can self-cut a groove in the bone so that the keel 1828 is locked into the bone as the keel 1828 is aligned by, and received in, a groove 1831 of the lateral mass plate 1820. Alternatively, a groove can be pre-cut in the bone to receive the keel 1828. As this occurs the bore 1829 of the locking plate 1824 aligns with the threaded bore 1831 of the lateral mass plate 1820 and a machine screw can be inserted to lock the locking plate relative to the lateral mass plate. This locking prevents the lateral mass plate 1820 and the natural or artificial facet joint spacer or inter-facet spacer 1810 from rotating and, as previously indicated, prevents the bone screw 1840 from backing out from the vertebra. Preferably the implant is between the C5 and C6 vertebrae level, or the C6 and C7 vertebrae level. It is noted that two implants preferably will be implanted at each level between vertebrae. That is, an implant 1800 will be placed in a right facet joint and also in a left facet joint when viewed from a posterior view point. This procedure can be used to increase or distract the foraminal area or dimension of the spine in an extension or in neutral position (without having a deleterious effect on cervical lordosis) and reduce the pressure on the nerves and blood vessels. At the same time this procedure preserves mobility of the facet joint.
  • FIGS. 26A-27B show a further embodiment of the implant of the invention, with the embodiment 2000 implanted in the cervical spine as depicted in FIGS. 27A and 27B. The implant 2000 comprises a first natural or artificial facet joint spacer or inter-facet spacer 2010 and a second natural or artificial facet joint spacer or inter-facet spacer 2010. Each natural or artificial facet joint spacer or inter-facet spacer can have a distal end 2012 that is tapered or wedge-shaped in a way that facilitates insertion into the cervical facet joints on both sides of two adjacent cervical vertebrae at the same level. The natural or artificial facet joint spacers or inter-facet spacers further can be dome-shaped, or convex on a superior surface 2013, to approximate the shape of the cervical facets of the cervical facet joints.
  • The first and second natural or artificial facet joint spacer or inter-facet spacer s 2010 are bridged together by a collar 2015. The collar 2015 passes between the spinous processes of the adjacent cervical vertebrae. As can be seen in FIG. 26B, the implant can preferably be “V” shaped or “boomerang” shaped. The entire implant 2000 or the collar 2015 of the implant can be made of a flexible material such as titanium, so that it is possible to bend the collar 2015 so that it conforms preferably to the shape of the lateral mass or the lamina of the cervical vertebrae of the patient and thereby holds the implant in place with the natural or artificial facet joint spacer or inter-facet spacer s 2010 inserted in the cervical facet joints. Bores 2029 are preferably are provided through implant 2000 adjacent to the natural or artificial facet joint spacer or inter-facet spacer 2010 respectively. These bores 2029 can receive bone screws to position the implant 2000 against the lateral mass or the lamina as shown in FIGS. 27A, 27B. The description of the embodiment 2100, in FIGS. 28A, 28B provide further details concerning the method of affixing the implant 2000 to the vertebrae. The implant 2100 also can be made of PEEK or other materials as described herein. Embodiment 2000 (the “boomerang” shape depicted in FIG. 27B) further can have a locking plate as, for example, the locking plate 1824 in FIG. 22A. The locking plate for embodiment 2000 (not shown) can have the same features as locking plate 1824, that is: (1) a probe 1826 that interacts with the bone screws to prevent the bone screws from backing out of the bone, the likely consequence of which would be displacement of the implant 2000; and (2) a keel 1828 with a chisel end to embed in the bone and thus to prevent rotational displacement of the implant. However, given the collar 2015 configuration of embodiment 2000, a chisel may not serve the same purpose as with the embodiments set forth above, which lack a collar stabilized by two bone screws. Therefore, a locking plate on embodiment 2000 can be provided without a keel.
  • FIGS. 28A and 28B depict a further embodiment of the implant of the invention 2100. In this embodiment 2100, the collar 2115 can be made of a flexible material such as titanium, of a substantially inflexible material, or of other materials described herein. Substantial flexibility can also be derived from connecting a first natural or artificial facet joint spacer or inter-facet spacer 2110 with the collar 2115 using a first hinge 2117, and connecting a second natural or artificial facet joint spacer or inter-facet spacer 2110 with the collar 2115 using a second hinge 2117. Using the first hinge 2117 and the second hinge 2117, the collar 2115 can be pivoted downward to conform to a particular patient's cervical spinal anatomy. In other words, the degree of pivoting will vary among different patients, and the first hinge 2117 and second hinge 2117 allow the implant 2100 to accommodate the variance.
  • In the hinged embodiment 2100, and similar to the embodiment 2000, the collar 2115 can have a first bore 2129 inferior to the first hinge 2117, and a second bore 2129 inferior to the second hinge 2117. A first bone screw penetrates the first bore 2130 and into the lateral mass or the lamina, and the second bone screw penetrates the second bore 2130 and into the lateral mass or the lamina, the first and second bone screws serving to anchor the implant. A bore, preferably in the lateral mass, can be drilled for the first bone screw and for the second bone screw. Alternatively, the bone screws can be self-tapping. A first locking plate similar to the plate 1924 (FIG. 25A) can be secured about the head of the first bone screw and a second locking plate can be secured about the head of the second bone screw to prevent displacement of the first and second bone screws 2140. The first locking plate can block the first bone screw with a probe and the second locking plate can block to the second bone screw with a probe.
  • It should be noted that embodiments 2000 and 2100 also can be configured for accommodating treatment of cervical spinal stenosis and other cervical spine ailments where only a single cervical facet joint between adjacent vertebrae requires an implant, i.e., where treatment is limited to one lateral facet joint. In that case, the collar 2015, 2115 extends medially without extending further to join a second natural or artificial facet joint spacer or inter-facet spacer 2010, 2110. For the hinged embodiment 2100, the implant comprises a single hinge 2117, and the collar 2115 has only one bore 2129 to accept one bone screw to secure the implant 2100.
  • FIGS. 29A-E, depict a sizing and distracting tool 2200 of the invention. Sizing tool 2200 has a handle 2203 and a distal head 2210 that is shaped as a natural or artificial facet joint spacer or inter-facet spacer (e.g., 1810) of an implant of the invention. That is, the head 2210 preferably will have essentially the same features as the natural or artificial facet joint spacer or inter-facet spacer 1810, but the dimensions of the head 2210 will vary from one tool 2200 to the next, in order to be able to use different versions of the sizing tool 2200 to determine the dimensions of the cervical facet joint that is to be treated and then to select an appropriately-sized implant. The head 2210 preferably can be used to distract the facet joint prior to the step of implanting the implant in the facet joint. In this regard, the head 2210 is rounded at the most distal point 2212, and can be a tapered to facilitate insertion into a cervical facet joint. The head 2210 also can have a slightly convex superior surface 2213, the degree of convexity varying among different sizing tools 2200 in order to determine the desired degree of convexity of an implant to be implanted in the cervical facet joint. The head 2210 may have a uniform thickness along a proximal mid-section 2216. Accordingly, the inferior surface 2215 preferably can be concave. Alternatively, the proximal mid-section 2212 maybe convex on the superior surface 1813 without being uniform in thickness. Thus, the inferior surface 2215 can be flat or planar. The head also can be curved.
  • The head 2210 has a stop 2218 to prevent over-insertion of the head 2210 of the sizing tool 2200 into the facet joint. The stop 2218 can be a ridge that separates the head 2210 from the handle 2203. Alternatively, the stop 2218 can be any structure that prevents insertion beyond the stop 2218, including pegs, teeth, and the like.
  • Different sizing tools 2200 covering a range of dimensions of the head 2210 can be inserted successively into a cervical facet joint to select the appropriate size of an implant to position in the cervical spine, with the appropriate convexity and concavity of the natural or artificial facet joint spacer or inter-facet spacer. Each preferably larger head also can be used to distract the facet joint.
  • FIG. 31A depicts a posterior view of a further embodiment 2300 of the implant of the invention. Embodiment 2300, as well as all of the embodiments herein, can benefit from some or all of the advantages described herein with regard to the other embodiments described herein. Further, FIG. 31A, embodiment 2300 has a natural or artificial facet joint spacer or inter-facet spacer 2310 that can have a tapered or thinned distal end 2312 so that the distal end 2312 facilitates insertion of the natural or artificial facet joint spacer or inter-facet spacer 2310 into a cervical facet joint. The distal end 2312 can be rounded, as seen in the plan view of FIG. 31A, in order to conform to the roundness of the facet joint. The natural or artificial facet joint spacer or inter-facet spacer 2310 further can be curved so that a superior surface 2313 of the natural or artificial facet joint spacer or inter-facet spacer 2310 is convex, and an inferior surface 2315 is concave, to approximate the natural shape of the cervical facet joint that is to receive the implant 2300. The curve can have a uniform thickness, or it can have a varied thickness. Further, the lateral edges of the natural or artificial facet joint spacer or inter-facet spacer 2310 are curved or rounded, for distribution of load-bearing stress. As with other embodiments described herein, the natural or artificial facet joint spacer or inter-facet spacer 2310 also can be made of a flexible, biocompatible material, such as PEEK, to maintain joint mobility and flexibility.
  • The natural or artificial facet joint spacer or inter-facet spacer 2310 is connected flexibly with a lateral mass plate 2320, the flexible connection preferably being a hinge 2322. As seen in the plan view of FIG. 31A, the implant 2300 is substantially hour-glass shaped. This shape, as well as the shape of FIG. 32, will be discussed further below. The hinge 2322 is narrower than the natural or artificial facet joint spacer or inter-facet spacer 2310, with the hinge 2322 sitting at substantially the isthmus 231 7between the natural or artificial facet joint spacer or inter-facet spacer 2310 and the lateral mass plate 2320. The curved edges, or fillets, about the hinge 2322 serve to distribute more evenly the load-bearing stress on the implant 2300, and thus prevent concentrating the stress about the edges.
  • The hinge 2322 allows the implant 2300 to bend at the hinge 2322, bringing a lateral mass plate 2320 adjacent to the lateral mass and/or lamina of the patient's spine, and to conform to a particular patient's anatomy. The lateral mass plate 2320 is made of a biocompatible flexible material, preferably titanium or any other biocompatible flexible material as described herein, for example PEEK, that will support the use of bone screws and other hardware, as described below. The lateral mass plate 2320 bends downward at the hinge 2322 over a wide range of angles relative to the natural or artificial facet joint spacer or inter-facet spacer 2310, and preferably at an angle of more than 90 degrees, and this flexibility facilitates positioning and insertion of the natural or artificial facet joint spacer or inter-facet spacer. This flexibility of the lateral mass plate 2320 relative to the natural or artificial facet joint spacer or inter-facet spacer 2310 further facilitates positioning of the lateral mass plate relative to the lateral mass and/or the lamina of the patient's spine. Once the lateral mass plate 2320 is positioned adjacent to the bone, preferably the lateral mass of a cervical vertebra, a first bone screw, such as bone screw 1840, can be inserted through a first bore 2330 through the lateral mass plate 2320 and embedded into the bone of the lateral mass of the cervical vertebra.
  • The lateral mass plate 2320 further comprises a second bore 2329 which is preferably positioned medially, relative to the first bore 2330. Thus, viewing the implant from a posterior perspective as in FIG. 31A, the second bore 2329 in the lateral mass plate 2320 can be positioned either to the left or to the right of the first bore 2330. The position of the second bore 2329 will depend upon whether the implant 2300 is intended to be inserted into a cervical facet joint on the left or right side of a patient. Specifically, an implant 2300 to be inserted into a right-side cervical facet joint (i.e., the patient's rights side) will have a second bore 2329 positioned to the left of the first bore 2330 as in FIG. 31A, when implant 2300 is viewed from a posterior perspective, while an implant 2300 to be inserted into a left-side cervical facet joint will have a second bore 2329 positioned to the right of the first bore 2330, when implant 2300 is viewed from a posterior perspective.
  • The second bore 2329 through the lateral mass plate 2320 is adapted to accept a second screw 2390 (FIG. 31B), which preferably is a locking screw with a chisel point 2391. The locking screw 2390 is received by the second bore 2329 and the chisel point 2391 self-cuts a bore into the bone. The locking screw 2390 preferably is inserted through the second bore 2329 and embedded in the bone, after the bone screw is embedded in the bone through the first bore 2330. The position of the second bore 2329, i.e., medial to the first bore 2330, positions the locking screw 2390 so that it embeds in stronger bone tissue than if the second bore 2329 were located more laterally. The locking screw, in combination with the bone screw, prevents rotational and/or backward displacement of the implant 2300. As the locking screw 2390 is received by the second bore 2329, the head 2392 of the locking screw 2390 aligns with the head of the first bone screw in the first bore 2330, blocking the head of the first bone screw to prevent the first bone screw from backing out of the bone of the vertebra and the first bore 2330.
  • FIG. 32 depicts a further embodiment 2400 of the implant of the invention, from a posterior view. Embodiment 2400 is adapted to be implanted in a manner that preserves the anatomy of the cervical facet joint, in particular, the soft tissues around the cervical facet joint, including the joint capsule.
  • Implant 2400, like implant 2300 and other implants disclosed above, has a natural or artificial facet joint spacer or inter-facet spacer 2410, flexibly connected, preferably by a hinge 2422, to a lateral mass plate 2420. As can be seen in FIG. 32, the implant 2400 including the natural or artificial facet joint spacer or inter-facet spacer 2410 and the hinge 2422 is substantially “P” shaped. As explained below, its “P” shape assists in the insertion of the implant 2400 into the facet joint with most of the facet capsule and facet capsule ligament and other soft tissue associated with the facet joint still left intact. The natural or artificial facet joint spacer or inter-facet spacer, as above for implant 2300 and the other implants disclosed above, can have a superior surface 2413 of the natural or artificial facet joint spacer or inter-facet spacer 2410 that is convex, and an inferior surface 2415 that is concave, or any appropriate shaping to approximate the natural shape of the cervical facet joint that is to receive the implant 2400. The thickness of the natural or artificial facet joint spacer or inter-facet spacer 2410 can be uniform, or varied. The natural or artificial facet joint spacer or inter-facet spacer 2410 also can be made of a flexible, biocompatible material, such as PEEK, to maintain joint mobility and flexibility. The hinge 2422 can have smooth, rounded edges, for distribution of load stress, as disclosed above. Other features and advantages of the other embodiments can be, if desired, incorporated into the design of the embodiment of FIG. 32. For example, the natural or artificial facet joint spacer or inter-facet spacer 2410 further can have a tapered or thinned edge 2412 so that the edge 2412 facilitates insertion of the natural or artificial facet joint spacer or inter-facet spacer 2410 into a cervical facet joint. The edge 2412 can be curved. In this embodiment 2400, however, the thinned edge 2412 of the natural or artificial facet joint spacer or inter-facet spacer 2410 preferably is not at the distal end of the natural or artificial facet joint spacer or inter-facet spacer 2400 as is the thinned edge 2312 of the natural or artificial facet joint spacer or inter-facet spacer 2300; rather, the thinned edge 2412 preferably is positioned laterally, toward the hinge 2422 of the implant 2400. The thinned edge 2412 coincides substantially with a lateral curvature 2440 of the natural or artificial facet joint spacer or inter-facet spacer 2410, which is pronounced relative to the curvature on the medial side of the implant 2400, i.e., a “P” shape. In other words, the curved part of the head of the “P” 2440 corresponds to the thinned edge 2412, and serves as the leading edge of the implant 2400 to begin insertion of the natural or artificial facet joint spacer or inter-facet spacer 2410 into a cervical facet joint, preferably through an incision in the soft tissue of the facet joint. The “P” shape narrows at isthmus 2417 where the natural or artificial facet joint spacer or inter-facet spacer 2410 that is joined by the hinge 2422 with the lateral mass plate 2420. The smooth or rounded edges or fillets serve to distribute stresses on the implant 2400. The above described “P” shape of implant 2400 allows the implant 2400 to be pivoted into place into a facet joint as described below. The thinned edge 2412 and leading lateral curvature 2440 of the natural or artificial facet joint spacer or inter-facet spacer 2410 are adapted to facilitate urging implant 2400 into the cervical facet joint, through the incision in the joint capsule. The implant 2400 then is pivoted into position so that the lateral mass plate 2420 can be bent downward, relative to the natural or artificial facet joint spacer or inter-facet spacer 2410, to align with and lie adjacent to the lateral mass and/or the lamina. The lateral mass plate 2420 is then fastened to the bone.
  • The lateral mass plate 2420 of implant 2400, like the lateral mass plate for implant 2300, is flexibly connected, preferably by the smooth-edged hinge 2422, to the natural or artificial facet joint spacer or inter-facet spacer 2410 at the narrow lower part of the natural or artificial facet joint spacer or inter-facet spacer. The lateral mass plate 2420 is made of a biocompatible flexible material, preferably titanium or any other biocompatible flexible material such as PEEK that will support the use of bone screws and other hardware, as described below.
  • The lateral mass plate 2420 bends downward at a wide range of angles relative to the natural or artificial facet joint spacer or inter-facet spacer 2410, and preferably at an angle of more than 90 degrees. The flexibility of the lateral mass plate 2420 relative to the natural or artificial facet joint spacer or inter-facet spacer 2410 further facilitates positioning of the lateral mass plate 2420 relative to the lateral mass and/or the lamina of the patient's spine.
  • Like embodiment 2300, described above, the lateral mass plate 2420 has first bore 2430, which is adapted to receive a bone screw 2440, to help anchor implant 2400 in position. The lateral mass plate 2420 further includes a second bore 2429 adapted to be positioned medially, relative to the first bore 2430, as disclosed above for implant 2300. The position of the second bore 2429, when viewing implant 2400 from a posterior perspective (FIG. 32), will depend upon whether implant 2400 is intended to be implanted into a left-side or right-side cervical facet joint of a patient. Thus, implant 2400 with the second bore 2429 positioned to the left of the first bore 2430 is intended to be implanted in a right-side cervical facet joint of a patient, as depicted in FIG. 32, while an implant 2400 with a second bore 2429 positioned to the right of the first bore 2430 is intended to be implanted in a left-side cervical facet joint of a patient.
  • The second bore 2429 through the lateral mass plate 2420 is adapted to receive a second screw 2490 with head 2492, which preferably is a locking screw with a chisel point, such as screw 2390. The function and purpose of the bone screw disposed through bore 2430 and the locking screw disposed through bore 2429 are as described above with respect to the implant 2300.
  • The present invention further includes a method of implanting the implant 2400 (FIGS. 33A, 33B). To insert the natural or artificial facet joint spacer or inter-facet spacer 2410, a facet joint is accessed and an incision or a pair of incisions is made in the capsular ligament, the joint capsule, and the synovial membrane so that the thinned edge 2412 of the implant 2400 can be urged into the cervical facet joint through these tissues. The capsular ligament and the joint capsule and other soft tissues around the cervical facet joint are allowed to remain substantially intact, except for the small incision, and will be sutured and allowed to heal around the implant 2400. If desired, the cervical facet joint can be distracted prior to urging the curved section 2440 with the thinned edge 2412 of the natural or artificial facet joint spacer or inter-facet spacer 2410 into the cervical facet joint. Once the curved section 2440 of the natural or artificial facet joint spacer or inter-facet spacer 2410 with the thinned edge 2412 is urged into the cervical facet joint, implant 2400 is pivoted, preferably about 90 degrees, so that the second bore 2429 is placed medially relative to the first bore 2430. This allows the natural or artificial facet joint spacer or inter-facet spacer 2410 to be positioned in the facet joint. It is noted that the overall size, including the isthmus 2417, of the artificial fact joint 2410, as that of 2310, can be somewhat smaller than in prior embodiments to allow the natural or artificial facet joint spacer or inter-facet spacer to be positioned within the edges of the facet joint with the joint capsule substantially intact. The lateral mass plate 2420 then can be bent downward about the hinge 2422 into position adjacent the lateral mass or lamina of the spine of the patient, which position will depend upon the anatomy of an individual patient's cervical spine.
  • Once the lateral mass plate 2420 is positioned adjacent to the bone, preferably the lateral mass of a cervical vertebra, a first bone screw can be inserted through the first bore 2430 through the lateral mass plate 2420 and become embedded into the bone of the lateral mass of the cervical vertebra to anchor the implant 2400. After the bone screw is embedded, a locking screw is inserted through the second bore 2429 of the lateral mass plate 2420, the second bore 2429 medial to the first bore 2430. The locking screw has a chisel end that allows the locking screw to dig into the bone without use of a tool to pre-cut a bore. Alternatively, a bore can be pre-cut and a locking screw without a chisel end can be used. As the locking screw is embedded in the bone, the locking head of the locking screw is brought into proximity with the head of the bone screw to block its backward movement so that the implant 2400 remains anchored with the bone screw, i.e., so that the bone screw cannot back out of the bone. The embedded locking screw also serves to prevent rotational displacement of implant 2400, while blocking backward displacement of the first bone screw.
  • FIG. 34A depicts a posterior view of another embodiment 2500 of the implant of the invention. Embodiment 2500, as well as all of the embodiments herein, can benefit from some or all of the features and advantages with regard to the other embodiments described herein. As shown, embodiment 2500 has a natural or artificial facet joint spacer or inter-facet spacer 2510 that can have a tapered or thinned distal end 2512. The natural or artificial facet joint spacer or inter-facet spacer 2510 further can be curved so that a superior surface 2513 of the natural or artificial facet joint spacer or inter-facet spacer 2510 is convex, and an inferior surface 2515 is concave, to approximate the natural shape of the cervical facet joint that is to receive the implant 2500. In one embodiment, the inferior surface 2515 is substantially flat whereby the superior surface 2513 is convex (FIG. 34B). As shown in FIG. 34B, the convex superior surface 2513 tapers downward at an increased angle toward the inferior surface 2515 at the distal end 2512. This contour of the superior surface 2513 aids in smooth insertion of the natural or artificial facet joint spacer or inter-facet spacer 2510 into the facet joint. As with other embodiments described above, the natural or artificial facet joint spacer or inter-facet spacer 2510 also can be made of a flexible, biocompatible material, such as PEEK, to maintain joint mobility and flexibility.
  • The natural or artificial facet joint spacer or inter-facet spacer 2510 is connected flexibly with the lateral mass plate 2520, preferably with a hinge 2522. The hinge 2522 allows the natural or artificial facet joint spacer or inter-facet spacer 2510 and the lateral mass plate 2520 of the implant 2500 to bend with respect to one another between an extended position and a bent or folded position as discussed above. Once the lateral mass plate 2520 is positioned adjacent to the bone, preferably the lateral mass of a cervical vertebra, a first bone screw, such as bone screw 1840, can be inserted through a first bore 2530 through the lateral mass plate 2520 and embedded into the bone of the lateral mass of the cervical vertebra. In addition, once the lateral mass plate 2520 is secured with the first bone screw, a second bone screw can be inserted through a second bore 2529 in the lateral mass plate 2520, whereby the second bone screw would be embedded into the bone of the lateral mass of the cervical vertebra. Details of the first and second bores are discussed above.
  • The lateral mass plate 2520 is made of a biocompatible flexible material, preferably titanium or any other biocompatible flexible material as described herein, for example PEEK, that will support the use of bone screws and other hardware, as described below. The lateral mass plate 2520 bends downward about the hinge 2522 over a wide range of angles relative to the natural or artificial facet joint spacer or inter-facet spacer 2510. In another embodiment, any other type of interface between the natural or artificial facet joint spacer or inter-facet spacer 2510 and the lateral mass plate 2520 is contemplated (e.g. ball and socket joint). This flexibility facilitates positioning and insertion of the natural or artificial facet joint spacer or inter-facet spacer 2510.
  • FIG. 34B depicts a side view of the natural or artificial facet joint spacer or inter-facet spacer and lateral mass plate in accordance with one embodiment. As shown in FIG. 34B, the natural or artificial facet joint spacer or inter-facet spacer 2510 includes an hyper-extension tab 2522 in one embodiment. The hyper-extension tab 2522 prevents the natural or artificial facet joint spacer or inter-facet spacer 2510 as well as the lateral mass plate 2520 from moving in a direction beyond the extended position which is shown in FIGS. 34A and 35B. The lateral mass plate 2520 preferably includes a recess 2511 at the interface between the lateral mass plate 2520 and the natural or artificial facet joint spacer or inter-facet spacer 2510 which seats the tab 2522 in the extended position which is shown in FIG. 34A. When the natural or artificial facet joint spacer or inter-facet spacer 2510 is bent at an angle, the tab 2522 is not in contact with the recess 2511. However, the tab 2522 comes into contact with the recess 2511 when in the extended position, as shown in FIG. 34A. In addition, the tab 2522, when seated in the recess 2511, prevents the natural or artificial facet joint spacer or inter-facet spacer 2510 and lateral mass plate 2520 from moving beyond the extended position. This features aids in placing the implant into the facet joint as the implant is prevented from bending back beyond the extended position shown in FIG. 34B. This arrangement, however, allows the lateral mass plate 2520 to bend down to meet the spine when the natural or artificial facet joint spacer or inter-facet spacer 2510 is implanted in the facet joint.
  • As shown in FIG. 34A, the lateral mass plate 2520 preferably includes a third bore 2502 located near a rear edge, whereby the third bore 2052 preferably receives an engaging rod 2616 (FIG. 35B) of an implantation tool 2600 described below. The third bore 2502 preferably extends through the superior and inferior surfaces of the lateral mass plate, although not necessarily. Although the third bore 2502 is circular in shape, any other shape is contemplated which engages a correspondingly shaped engaging rod 2616 (FIG. 35B). The rear edge 2504 of the lateral mass plate 2520 can be engaged by the engagement head 2606 (FIG. 35B) of the implantation tool 2600 as described below.
  • In addition, the lateral mass plate 2520 preferably includes one or more winged protrusions, such as tabs, wing lets or ears, 2508 which protrude from the side edges of the lateral mass plate 2520. FIG. 34A illustrates the implant 2500 having two winged protrusions 2508. The protrusions 2508 serve as guides to successfully couple the implant 2500 to the implantation tool 2600. In addition, the protrusions act as an engaging mechanism which secures the implant 2500 to the tool 2600. It should be noted that the winged protrusions 2508 are preferred and the implant 2500 can be configured in any other appropriate design to ensure that the implant 2500 is able to be effectively guided and secured to the implantation tool 2600.
  • FIG. 35A depicts an implantation tool in accordance with one embodiment of the present invention. As shown in FIG. 35A, the tool 2600 preferably includes a handle 2602 having a proximal end and a distal end. The tool 2600 includes an actuating switch 2608 as well as a shaft 2604 extending from the distal end of the handle 2602. As shown in FIG. 35A, the shaft 2604 preferably extends axially with the handle 2602, although the shaft 2604 may be at an angle with respect to the handle 2602. Extending from the shaft 2604 is an engagement head 2606, whereby the engagement head is preferably oriented at an angle with respect to the shaft 2604 and/or the handle 2602. The angle of the head 2606 relative to the shaft 2604 aids the surgeon in the process of implanting the implant 2500 in the spine. This angle allows the surgeon to slip the natural or artificial facet joint spacer or inter-facet spacer 2510 into the facet joint with the tool 2600 preferably about a right angle to the spine. Preferably the head is at an angle between 45 and 90 degrees relative to the handle 2604. However, other angles are contemplated.
  • Referring to FIG. 35B, the engagement head 2606 preferably has a forked configuration and includes a pair of side walls 2610, an engagement seat 2612 as well as a receiving space 2618 which is defined as the area between the side walls 2610 and the seat 2612. The engagement head 2606 preferably includes a retractable engaging rod 2616 which extends partially into the receiving space 2618. The side walls 2610 each have an inner side which includes a slot 2612 whereby the slots 2612 face the receiving space 2618. The slots 2612 are dimensioned to slidably receive the wing protrusions 2508 of the lateral mass plate 2520 as well as secure the lateral mass plate 2520 to the engagement head 2606. The engagement seat 2612 receives the rear edge 2504 of the lateral mass plate 2520.
  • In one embodiment, the engagement head 2606 preferably includes the engaging rod 2616, as shown in FIG. 35B. The engaging rod 2616 is dimensioned to fit within the third bore 2502 in the lateral mass plate 2520. The engaging rod 2616 is coupled the switch 2608 on the handle 2602, whereby actuation of the switch 2608 causes the engaging rod 2616 to retract. Upon being retracted, the engaging rod 2616 disengages the third bore 2502 and allows the implant 2500 to be disengaged from the engagement head 2606. It is preferred that the tool 2600 includes a spring or other urging means to urge the engaging rod 2616 to the extended position, as shown in FIG. 35B. In another embodiment, the engaging rod 2616 is freely moveable between the extended and retracted positions without a biasing force applied thereto.
  • It should be noted that the engaging rod 2616 is shown as being a circular cylinder in FIGS. 35A and 35B. However, it is contemplated that the engaging rod 2616 can have any other shape which conforms to the shape of the third bore 2502 in the lateral mass plate 2520. In another embodiment, the engagement head 2606 does not include an engaging rod 2616 but some other mechanism to secure the implant 2500 to the tool 2600. In yet another embodiment, the slots 2612 in the side walls 2610 can be used to retain the implant 2500 in the head 2606 without the use of an engaging mechanism.
  • In preferred operation, to engage the implant 2500 with the tool 2600, the implant 2600 is oriented to be right side up such that the rear surface 2504 of the implant 2500 will conform and mate with the engagement seat 2614. The implant 2500 is aligned with the forked portion of the engagement head 2606, whereby the winged protrusions 2508 of the implant 2500 are inserted into the slot openings 2612. Upon registering the winged protrusions 2508 into the corresponding slots 2612, the lateral mass plate 2520 is guided into engagement by the slots 2612 until the rear edge 2504 mates with the engagement seat 2614. Preferably the engaging rod 2616 is then inserted into the third bore 2502, thereby securing the lateral mass plate 2520 to the engagement head 2606. In one embodiment, the user manually actuates the switch 2608 to retract the engaging rod 2616 to allow the lateral mass plate 2520 to be inserted completely in the receiving space. The switch 2608 is then manually released when the bore 2502 and engaging rod 2616 are aligned such that the engaging rod 2616 then extends and engages the third bore 2502. In another embodiment, contact between the superior surface of the lateral mass plate 2520 and the engaging rod 2616 causes the engaging rod 2616 to slightly retract while the plate 2520 is moved into the engagement seat 2614. Once the lateral mass plate 2520 is seated, the third bore 2502 preferably registers with the engaging rod 2616, whereby the urging force causes the engaging rod 2616 to automatically engage the third bore 2502.
  • During the surgical procedure, the natural or artificial facet joint spacer or inter-facet spacer 2510 is inserted into the distracted facet joint as described in detail above. Upon the natural or artificial facet joint spacer or inter-facet spacer 2510being satisfactorily inserted in the facet joint, the user preferably actuates the switch 2608 to disengage the engaging rod 2616 from the third bore 2502. The surgeon then draws the tool 2600 away from the facet joint, whereby the lateral mass plate 2520 slides out of the received area and is guided by the slots 2612. The lateral mass plate 2520 is then anchored into the vertebral body as discussed above.
  • The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations will be apparent to practitioners skilled in this art. The embodiments were chosen and described in order to explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.

Claims (19)

1. A facet joint implant adapted to be inserted into a facet joint, the implant comprising:
a. a facet joint spacer; and
b. an anchoring plate associated with the facet joint spacer, wherein the anchoring plate includes an engagement aperture adapted to receive a retractable engaging member of an implanting tool.
2. The implant of claim 1 wherein the engagement aperture is in a superior surface of the anchoring plate.
3. The implant of claim 1 wherein the anchoring plate further comprises a side surface having an protrusion adapted to correspondingly register in a receiving slot in the implanting tool.
4. The implant of claim 1 wherein the anchoring plate further comprises a pair of winged protrusions along opposing side surfaces, wherein the protrusions are adapted to register in corresponding slots in the implanting tool.
5. The implant of claim 1 wherein the anchoring plate further comprises:
a. a bone screw aperture adapted to receive a bone screw; and
b. a locking screw aperture adapted to receive a locking screw, the bone screw and locking screw adapted to anchor the anchoring plate into a vertebral body.
6. The implant of claim 1 wherein the facet joint spacer further comprises a substantially flat inferior surface and a convex superior surface, wherein the superior surface tapers toward the inferior surface at a front edge.
7. The implant of claim 1 wherein the facet joint spacer is flexibly movable between a nonextended position and an extended position with respect to the anchoring plate, wherein the facet joint spacer is unable to pivot beyond the extended position.
8. A facet joint implant adapted to be inserted in a facet joint, the implant comprising:
a. a facet joint spacer; and
b. an anchoring plate flexibly coupled to the facet joint spacer, the anchoring plate having a superior surface and an inferior surface, wherein the anchoring plate includes an aperture through the superior surface adapted to receive a retractable engaging member of an implanting tool, the anchoring plate including a protrusion on a side surface adapted to correspondingly register with a receiving slot of the implanting tool.
9. The implant of claim 8 wherein the protrusion further comprises a pair of winged protrusions along opposing side surfaces of the anchoring plate, wherein the protrusions are adapted to register in corresponding slots in the implanting tool.
10. The implant of claim 8 wherein the anchoring plate further comprises:
a. a bone screw aperture adapted to receive a bone screw; and
b. a locking screw aperture adapted to receive a locking screw, the bone screw and locking screw adapted to anchor the anchoring plate into a vertebral body.
11. The implant of claim 8 wherein the facet joint spacer further comprises a substantially flat inferior surface and a convex superior surface, wherein the superior surface tapers toward the inferior surface at a front edge.
12. The implant of claim 8 wherein the facet joint spacer is flexibly movable between a nonextended position and an extended position with respect to the anchoring plate, wherein the facet joint spacer is unable to pivot beyond the extended position.
13. A facet joint implant adapted to be inserted in a facet joint, the implant comprising:
a. a facet joint spacer; and
b. an anchoring plate flexibly coupled to the facet joint spacer, the anchoring plate having a superior surface and an inferior surface, wherein the anchoring plate includes a protrusion on a side surface adapted to correspondingly register with a receiving slot of the implanting tool.
14. The implant of claim 13 further comprising an engagement aperture adapted to receive a retractable engagement member of the implanting tool.
15. The implant of claim 14 wherein the engagement aperture is in a superior surface of the anchoring plate.
16. The implant of claim 13 wherein the protrusion further comprises a pair of winged protrusions along opposing side surfaces of the anchoring plate, wherein the protrusions are adapted to register in corresponding slots in the implanting tool.
17. The implant of claim 13 wherein the anchoring plate further comprises:
a. a bone screw aperture adapted to receive a bone screw; and
b. a locking screw aperture adapted to receive a locking screw, the bone screw and locking screw adapted to anchor the anchoring plate into a vertebral body.
18. The implant of claim 13 wherein the facet joint spacer further comprises a substantially flat inferior surface and a convex superior surface, wherein the superior surface tapers toward the inferior surface at a front edge.
19. The implant of claim 13 wherein the facet joint spacer is flexibly movable between a nonextended position and an extended position with respect to the anchoring plate, wherein the facet joint spacer is unable to pivot beyond the extended position.
US11/429,733 2004-12-13 2006-05-08 Inter-cervical facet implant with implantation tool Active 2029-11-25 US8029540B2 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US11/429,733 US8029540B2 (en) 2005-05-10 2006-05-08 Inter-cervical facet implant with implantation tool
US11/447,413 US8118838B2 (en) 2004-12-13 2006-06-06 Inter-cervical facet implant with multiple direction articulation joint and method for implanting
US13/197,841 US8425530B2 (en) 2004-12-13 2011-08-04 Apparatus for sizing a facet joint

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US67937705P 2005-05-10 2005-05-10
US11/429,733 US8029540B2 (en) 2005-05-10 2006-05-08 Inter-cervical facet implant with implantation tool

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US11/304,436 Continuation-In-Part US20060247633A1 (en) 2004-12-13 2005-12-14 Inter-cervical facet implant with surface enhancements

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US13/197,841 Continuation US8425530B2 (en) 2004-12-13 2011-08-04 Apparatus for sizing a facet joint

Publications (3)

Publication Number Publication Date
US20070016195A1 US20070016195A1 (en) 2007-01-18
US20070244483A9 true US20070244483A9 (en) 2007-10-18
US8029540B2 US8029540B2 (en) 2011-10-04

Family

ID=37662600

Family Applications (2)

Application Number Title Priority Date Filing Date
US11/429,733 Active 2029-11-25 US8029540B2 (en) 2004-12-13 2006-05-08 Inter-cervical facet implant with implantation tool
US13/197,841 Active 2025-05-17 US8425530B2 (en) 2004-12-13 2011-08-04 Apparatus for sizing a facet joint

Family Applications After (1)

Application Number Title Priority Date Filing Date
US13/197,841 Active 2025-05-17 US8425530B2 (en) 2004-12-13 2011-08-04 Apparatus for sizing a facet joint

Country Status (1)

Country Link
US (2) US8029540B2 (en)

Cited By (51)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050261680A1 (en) * 2001-03-28 2005-11-24 Imperial College Innovations Ltd. Bone fixated, articulated joint load control device
US20080208341A1 (en) * 2006-12-29 2008-08-28 Providence Medical Technology, Inc. Cervical distraction method
US20080275559A1 (en) * 2007-05-01 2008-11-06 Exploramed Nc4, Inc. Adjustable absorber designs for implantable device
US20080275560A1 (en) * 2007-05-01 2008-11-06 Exploramed Nc4, Inc. Femoral and tibial base components
US20090276052A1 (en) * 2008-04-30 2009-11-05 Exploramed Nc4, Inc. Ball and socket assembly
US7655041B2 (en) 2007-05-01 2010-02-02 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems and implantation method
US20100082065A1 (en) * 2008-10-01 2010-04-01 Butler Michael S Spinal Facet Fastener
US7815648B2 (en) 2004-06-02 2010-10-19 Facet Solutions, Inc Surgical measurement systems and methods
US7914560B2 (en) 2004-02-17 2011-03-29 Gmedelaware 2 Llc Spinal facet implant with spherical implant apposition surface and bone bed and methods of use
US20110152932A1 (en) * 2009-12-21 2011-06-23 Industrial Technology Research Institute Flexible Spine Fixing Structure
US20110160771A1 (en) * 2009-12-31 2011-06-30 Industrial Technology Research Institute Flexible Spine Fixing Structure
US8123805B2 (en) 2007-05-01 2012-02-28 Moximed, Inc. Adjustable absorber designs for implantable device
US8206418B2 (en) 2007-01-10 2012-06-26 Gmedelaware 2 Llc System and method for facet joint replacement with detachable coupler
US8267966B2 (en) 2008-06-06 2012-09-18 Providence Medical Technology, Inc. Facet joint implants and delivery tools
US8361152B2 (en) 2008-06-06 2013-01-29 Providence Medical Technology, Inc. Facet joint implants and delivery tools
US8512347B2 (en) 2008-06-06 2013-08-20 Providence Medical Technology, Inc. Cervical distraction/implant delivery device
US8597362B2 (en) 2009-08-27 2013-12-03 Cotera, Inc. Method and apparatus for force redistribution in articular joints
US8696708B2 (en) 2008-03-06 2014-04-15 DePuy Synthes Products, LLC Facet interference screw
US8702758B2 (en) 2009-12-31 2014-04-22 Industrial Technology Research Institute Flexible spine fixing structure
US8709090B2 (en) 2007-05-01 2014-04-29 Moximed, Inc. Adjustable absorber designs for implantable device
US20140156004A1 (en) * 2009-08-27 2014-06-05 Cotera, Inc. Method and Apparatus for Altering Biomechanics of the Articular Joints
US8777994B2 (en) 2004-06-02 2014-07-15 Gmedelaware 2 Llc System and method for multiple level facet joint arthroplasty and fusion
US8801795B2 (en) 2007-05-01 2014-08-12 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems
US8894714B2 (en) 2007-05-01 2014-11-25 Moximed, Inc. Unlinked implantable knee unloading device
US8986355B2 (en) 2010-07-09 2015-03-24 DePuy Synthes Products, LLC Facet fusion implant
US9005288B2 (en) 2008-01-09 2015-04-14 Providence Medical Techonlogy, Inc. Methods and apparatus for accessing and treating the facet joint
US9044270B2 (en) 2011-03-29 2015-06-02 Moximed, Inc. Apparatus for controlling a load on a hip joint
USD745156S1 (en) 2012-10-23 2015-12-08 Providence Medical Technology, Inc. Spinal implant
WO2015184012A3 (en) * 2014-05-27 2016-03-31 Providence Medical Technology, Inc. Lateral mass fixation implant
US9333086B2 (en) 2008-06-06 2016-05-10 Providence Medical Technology, Inc. Spinal facet cage implant
US9381049B2 (en) 2008-06-06 2016-07-05 Providence Medical Technology, Inc. Composite spinal facet implant with textured surfaces
US9398957B2 (en) 2007-05-01 2016-07-26 Moximed, Inc. Femoral and tibial bases
US9468466B1 (en) 2012-08-24 2016-10-18 Cotera, Inc. Method and apparatus for altering biomechanics of the spine
US9668868B2 (en) 2009-08-27 2017-06-06 Cotera, Inc. Apparatus and methods for treatment of patellofemoral conditions
US9861408B2 (en) 2009-08-27 2018-01-09 The Foundry, Llc Method and apparatus for treating canine cruciate ligament disease
US9907645B2 (en) 2007-05-01 2018-03-06 Moximed, Inc. Adjustable absorber designs for implantable device
US10201375B2 (en) 2014-05-28 2019-02-12 Providence Medical Technology, Inc. Lateral mass fixation system
USD841165S1 (en) 2015-10-13 2019-02-19 Providence Medical Technology, Inc. Cervical cage
US10349980B2 (en) 2009-08-27 2019-07-16 The Foundry, Llc Method and apparatus for altering biomechanics of the shoulder
US10383736B2 (en) 2007-05-01 2019-08-20 Moximed, Inc. Femoral and tibial base components
USD887552S1 (en) 2016-07-01 2020-06-16 Providence Medical Technology, Inc. Cervical cage
US10682243B2 (en) 2015-10-13 2020-06-16 Providence Medical Technology, Inc. Spinal joint implant delivery device and system
USD911525S1 (en) 2019-06-21 2021-02-23 Providence Medical Technology, Inc. Spinal cage
USRE48501E1 (en) 2012-10-23 2021-04-06 Providence Medical Technology, Inc. Cage spinal implant
US11065039B2 (en) 2016-06-28 2021-07-20 Providence Medical Technology, Inc. Spinal implant and methods of using the same
USD933230S1 (en) 2019-04-15 2021-10-12 Providence Medical Technology, Inc. Cervical cage
US11224521B2 (en) 2008-06-06 2022-01-18 Providence Medical Technology, Inc. Cervical distraction/implant delivery device
USD945621S1 (en) 2020-02-27 2022-03-08 Providence Medical Technology, Inc. Spinal cage
US11272964B2 (en) 2008-06-06 2022-03-15 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US11648128B2 (en) 2018-01-04 2023-05-16 Providence Medical Technology, Inc. Facet screw and delivery device
US11871968B2 (en) 2017-05-19 2024-01-16 Providence Medical Technology, Inc. Spinal fixation access and delivery system

Families Citing this family (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8267969B2 (en) * 2004-10-20 2012-09-18 Exactech, Inc. Screw systems and methods for use in stabilization of bone structures
US8025680B2 (en) * 2004-10-20 2011-09-27 Exactech, Inc. Systems and methods for posterior dynamic stabilization of the spine
US8162985B2 (en) * 2004-10-20 2012-04-24 The Board Of Trustees Of The Leland Stanford Junior University Systems and methods for posterior dynamic stabilization of the spine
US7935134B2 (en) * 2004-10-20 2011-05-03 Exactech, Inc. Systems and methods for stabilization of bone structures
US8226690B2 (en) * 2005-07-22 2012-07-24 The Board Of Trustees Of The Leland Stanford Junior University Systems and methods for stabilization of bone structures
US20070239159A1 (en) * 2005-07-22 2007-10-11 Vertiflex, Inc. Systems and methods for stabilization of bone structures
CA2614898C (en) * 2005-04-27 2014-04-22 Trinity Orthopedics, Llc Mono-planar pedilcle screw method, system, and kit
US8523865B2 (en) 2005-07-22 2013-09-03 Exactech, Inc. Tissue splitter
US20070055373A1 (en) * 2005-09-08 2007-03-08 Zimmer Spine, Inc. Facet replacement/spacing and flexible spinal stabilization
US8096996B2 (en) 2007-03-20 2012-01-17 Exactech, Inc. Rod reducer
US8133261B2 (en) 2007-02-26 2012-03-13 Depuy Spine, Inc. Intra-facet fixation device and method of use
US8894685B2 (en) 2007-04-13 2014-11-25 DePuy Synthes Products, LLC Facet fixation and fusion screw and washer assembly and method of use
US8197513B2 (en) 2007-04-13 2012-06-12 Depuy Spine, Inc. Facet fixation and fusion wedge and method of use
US8043334B2 (en) * 2007-04-13 2011-10-25 Depuy Spine, Inc. Articulating facet fusion screw
US8088163B1 (en) 2008-02-06 2012-01-03 Kleiner Jeffrey B Tools and methods for spinal fusion
US9636121B2 (en) * 2008-11-11 2017-05-02 Harbinger Medical Group, Llc Facet distraction device, facet joint implant, and associated methods
US8366748B2 (en) * 2008-12-05 2013-02-05 Kleiner Jeffrey Apparatus and method of spinal implant and fusion
US9247943B1 (en) 2009-02-06 2016-02-02 Kleiner Intellectual Property, Llc Devices and methods for preparing an intervertebral workspace
US20100234905A1 (en) * 2009-03-13 2010-09-16 John Sledge Facet joint resurfacing implant and associated surgical methods
US10245159B1 (en) 2009-09-18 2019-04-02 Spinal Surgical Strategies, Llc Bone graft delivery system and method for using same
US10973656B2 (en) 2009-09-18 2021-04-13 Spinal Surgical Strategies, Inc. Bone graft delivery system and method for using same
US8906028B2 (en) 2009-09-18 2014-12-09 Spinal Surgical Strategies, Llc Bone graft delivery device and method of using the same
WO2011050140A1 (en) 2009-10-22 2011-04-28 Blue Fury Consulting, L.L.C. Posterior cervical fusion system and techniques
US10098674B2 (en) 2009-10-22 2018-10-16 Nuvasive, Inc. System and method for posterior cervical fusion
US9044277B2 (en) 2010-07-12 2015-06-02 DePuy Synthes Products, Inc. Pedicular facet fusion screw with plate
WO2012154653A1 (en) * 2011-05-10 2012-11-15 Synthes Usa, Llc Facet interference cage
US8795285B2 (en) 2011-10-19 2014-08-05 Brian Kwon Spinal facet fusion device and method of operation
FR2984781B1 (en) * 2011-12-22 2014-01-24 Commissariat Energie Atomique PROCESS FOR THE BRAZING ASSEMBLY OF A SUBSTRATE COMPRISING PYROCARBON WITH PARTS COMPRISING PYROCARBON
US9295488B2 (en) 2012-08-09 2016-03-29 Wilson T. Asfora Joint fusion
US10278742B2 (en) 2012-11-12 2019-05-07 DePuy Synthes Products, Inc. Interbody interference implant and instrumentation
US9763705B2 (en) * 2014-10-03 2017-09-19 Globus Medical, Inc. Orthopedic stabilization devices and methods for installation thereof
CA3019527A1 (en) 2016-03-29 2017-10-05 Restorative Spine, LLC Facet joint replacement device and methods of use
ITUA20164453A1 (en) * 2016-06-16 2017-12-16 Piero Petrini Intervertebral joint partial endoprosthesis
US20200289285A1 (en) * 2017-11-16 2020-09-17 Providence Medical Technology, Inc. Arthroplasty implant for a facet joint
EP3727174B1 (en) * 2017-12-18 2022-01-26 G & G S.r.l. Improved partial endoprosthesis device for a vertebral joint
US10687955B2 (en) 2018-02-02 2020-06-23 Ayman H. Al-Jazaeri Distally expanding facet implant with integrated plate and delivery device
US11298244B2 (en) 2019-01-31 2022-04-12 K2M, Inc. Interbody implants and instrumentation
US11793558B2 (en) 2019-08-30 2023-10-24 K2M, Inc. All in one plate holder and spring loaded awl
US11534307B2 (en) 2019-09-16 2022-12-27 K2M, Inc. 3D printed cervical standalone implant
US11000384B2 (en) 2019-10-15 2021-05-11 Ayman H. Al-Jazaeri Distally expanding facet joint implant and delivery device

Citations (95)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3867728A (en) * 1971-12-30 1975-02-25 Cutter Lab Prosthesis for spinal repair
US3875595A (en) * 1974-04-15 1975-04-08 Edward C Froning Intervertebral disc prosthesis and instruments for locating same
US3879767A (en) * 1972-01-26 1975-04-29 Cutter Lab Prosthesis for articulating body structures
US4001896A (en) * 1975-06-09 1977-01-11 Zimmer, U.S.A. Inc. Prosthetic joint for total knee replacement
US4085466A (en) * 1974-11-18 1978-04-25 National Research Development Corporation Prosthetic joint device
US4156296A (en) * 1977-04-08 1979-05-29 Bio-Dynamics, Inc. Great (large) toe prosthesis and method of implanting
US4349921A (en) * 1980-06-13 1982-09-21 Kuntz J David Intervertebral disc prosthesis
US4502161A (en) * 1981-09-21 1985-03-05 Wall W H Prosthetic meniscus for the repair of joints
US4759769A (en) * 1987-02-12 1988-07-26 Health & Research Services Inc. Artificial spinal disc
US4772287A (en) * 1987-08-20 1988-09-20 Cedar Surgical, Inc. Prosthetic disc and method of implanting
US4863477A (en) * 1987-05-12 1989-09-05 Monson Gary L Synthetic intervertebral disc prosthesis
US4911718A (en) * 1988-06-10 1990-03-27 University Of Medicine & Dentistry Of N.J. Functional and biocompatible intervertebral disc spacer
US5015255A (en) * 1989-05-10 1991-05-14 Spine-Tech, Inc. Spinal stabilization method
US5047055A (en) * 1990-12-21 1991-09-10 Pfizer Hospital Products Group, Inc. Hydrogel intervertebral disc nucleus
US5092866A (en) * 1989-02-03 1992-03-03 Breard Francis H Flexible inter-vertebral stabilizer as well as process and apparatus for determining or verifying its tension before installation on the spinal column
US5127912A (en) * 1990-10-05 1992-07-07 R. Charles Ray Sacral implant system
US5147404A (en) * 1987-12-07 1992-09-15 Downey Ernest L Vertebra prosthesis
US5192326A (en) * 1990-12-21 1993-03-09 Pfizer Hospital Products Group, Inc. Hydrogel bead intervertebral disc nucleus
US5300073A (en) * 1990-10-05 1994-04-05 Salut, Ltd. Sacral implant system
US5306275A (en) * 1992-12-31 1994-04-26 Bryan Donald W Lumbar spine fixation apparatus and method
US5306309A (en) * 1992-05-04 1994-04-26 Calcitek, Inc. Spinal disk implant and implantation kit
US5306308A (en) * 1989-10-23 1994-04-26 Ulrich Gross Intervertebral implant
US5401269A (en) * 1992-03-13 1995-03-28 Waldemar Link Gmbh & Co. Intervertebral disc endoprosthesis
US5415661A (en) * 1993-03-24 1995-05-16 University Of Miami Implantable spinal assist device
US5425773A (en) * 1992-01-06 1995-06-20 Danek Medical, Inc. Intervertebral disk arthroplasty device
US5437672A (en) * 1992-11-12 1995-08-01 Alleyne; Neville Spinal cord protection device
US5445639A (en) * 1989-05-10 1995-08-29 Spine-Tech, Inc. Intervertebral reamer construction
US5458643A (en) * 1991-03-29 1995-10-17 Kyocera Corporation Artificial intervertebral disc
US5458642A (en) * 1994-01-18 1995-10-17 Beer; John C. Synthetic intervertebral disc
US5491882A (en) * 1993-12-28 1996-02-20 Walston; D. Kenneth Method of making joint prosthesis having PTFE cushion
US5514180A (en) * 1994-01-14 1996-05-07 Heggeness; Michael H. Prosthetic intervertebral devices
US5527312A (en) * 1994-08-19 1996-06-18 Salut, Ltd. Facet screw anchor
US5527314A (en) * 1993-01-04 1996-06-18 Danek Medical, Inc. Spinal fixation system
US5534030A (en) * 1993-02-09 1996-07-09 Acromed Corporation Spine disc
US5534028A (en) * 1993-04-20 1996-07-09 Howmedica, Inc. Hydrogel intervertebral disc nucleus with diminished lateral bulging
US5545229A (en) * 1988-08-18 1996-08-13 University Of Medicine And Dentistry Of Nj Functional and biocompatible intervertebral disc spacer containing elastomeric material of varying hardness
US5556431A (en) * 1992-03-13 1996-09-17 B+E,Uml U+Ee Ttner-Janz; Karin Intervertebral disc endoprosthesis
US5591165A (en) * 1992-11-09 1997-01-07 Sofamor, S.N.C. Apparatus and method for spinal fixation and correction of spinal deformities
US5603713A (en) * 1991-09-24 1997-02-18 Aust; Gilbert M. Anterior lumbar/cervical bicortical compression plate
US5645597A (en) * 1995-12-29 1997-07-08 Krapiva; Pavel I. Disc replacement method and apparatus
US5645599A (en) * 1994-07-26 1997-07-08 Fixano Interspinal vertebral implant
US5653762A (en) * 1994-03-18 1997-08-05 Pisharodi; Madhavan Method of stabilizing adjacent vertebrae with rotating, lockable, middle-expanded intervertebral disk stabilizer
US5674295A (en) * 1994-10-17 1997-10-07 Raymedica, Inc. Prosthetic spinal disc nucleus
US5674296A (en) * 1994-11-14 1997-10-07 Spinal Dynamics Corporation Human spinal disc prosthesis
US5676701A (en) * 1993-01-14 1997-10-14 Smith & Nephew, Inc. Low wear artificial spinal disc
US5716413A (en) * 1995-10-11 1998-02-10 Osteobiologics, Inc. Moldable, hand-shapable biodegradable implant material
US5741261A (en) * 1996-06-25 1998-04-21 Sdgi Holdings, Inc. Minimally invasive spinal surgical methods and instruments
US5766251A (en) * 1992-03-13 1998-06-16 Tomihisa Koshino Wedge-shaped spacer for correction of deformed extremities
US5766253A (en) * 1996-01-16 1998-06-16 Surgical Dynamics, Inc. Spinal fusion device
US5824093A (en) * 1994-10-17 1998-10-20 Raymedica, Inc. Prosthetic spinal disc nucleus
US5824094A (en) * 1997-10-17 1998-10-20 Acromed Corporation Spinal disc
US5868745A (en) * 1992-11-12 1999-02-09 Alleyne; Neville Spinal protection device
US5876404A (en) * 1997-01-02 1999-03-02 St. Francis Medical Technologies, Llc Spine distraction implant and method
US5879396A (en) * 1993-12-28 1999-03-09 Walston; D. Kenneth Joint prosthesis having PTFE cushion
US5893889A (en) * 1997-06-20 1999-04-13 Harrington; Michael Artificial disc
USRE36221E (en) * 1989-02-03 1999-06-01 Breard; Francis Henri Flexible inter-vertebral stabilizer as well as process and apparatus for determining or verifying its tension before installation on the spinal column
US5951555A (en) * 1996-03-27 1999-09-14 Rehak; Lubos Device for the correction of spinal deformities
US6014588A (en) * 1998-04-07 2000-01-11 Fitz; William R. Facet joint pain relief method and apparatus
US6019792A (en) * 1998-04-23 2000-02-01 Cauthen Research Group, Inc. Articulating spinal implant
US6039763A (en) * 1998-10-27 2000-03-21 Disc Replacement Technologies, Inc. Articulating spinal disc prosthesis
US6048342A (en) * 1997-01-02 2000-04-11 St. Francis Medical Technologies, Inc. Spine distraction implant
US6063121A (en) * 1998-07-29 2000-05-16 Xavier; Ravi Vertebral body prosthesis
US6066325A (en) * 1996-08-27 2000-05-23 Fusion Medical Technologies, Inc. Fragmented polymeric compositions and methods for their use
US6068630A (en) * 1997-01-02 2000-05-30 St. Francis Medical Technologies, Inc. Spine distraction implant
USRE36758E (en) * 1995-03-16 2000-06-27 Fitz; William R. Artificial facet joint
US6080157A (en) * 1995-09-12 2000-06-27 Cg Surgical Limited Device to stabilize the lamina
US6099531A (en) * 1998-08-20 2000-08-08 Bonutti; Peter M. Changing relationship between bones
US6113637A (en) * 1998-10-22 2000-09-05 Sofamor Danek Holdings, Inc. Artificial intervertebral joint permitting translational and rotational motion
US6200322B1 (en) * 1999-08-13 2001-03-13 Sdgi Holdings, Inc. Minimal exposure posterior spinal interbody instrumentation and technique
US20010018614A1 (en) * 1999-03-16 2001-08-30 Bianchi John R. Implants for orthopedic applications
US6293949B1 (en) * 2000-03-01 2001-09-25 Sdgi Holdings, Inc. Superelastic spinal stabilization system and method
US20020029039A1 (en) * 1997-01-02 2002-03-07 Zucherman James F. Supplemental spine fixation device and methods
US6419703B1 (en) * 2001-03-01 2002-07-16 T. Wade Fallin Prosthesis for the replacement of a posterior element of a vertebra
US6436101B1 (en) * 1999-10-13 2002-08-20 James S. Hamada Rasp for use in spine surgery
US20030004572A1 (en) * 2001-03-02 2003-01-02 Goble E. Marlowe Method and apparatus for spine joint replacement
US6565605B2 (en) * 2000-12-13 2003-05-20 Medicinelodge, Inc. Multiple facet joint replacement
US6579319B2 (en) * 2000-11-29 2003-06-17 Medicinelodge, Inc. Facet joint replacement
US6579318B2 (en) * 2000-06-12 2003-06-17 Ortho Development Corporation Intervertebral spacer
US6610091B1 (en) * 1999-10-22 2003-08-26 Archus Orthopedics Inc. Facet arthroplasty devices and methods
US20040059429A1 (en) * 2002-09-20 2004-03-25 Uri Amin Mechanically attached elastomeric cover for prosthesis
US20040116927A1 (en) * 2000-12-01 2004-06-17 Henry Graf Intervertebral stabilizing device
US20040127989A1 (en) * 2002-12-31 2004-07-01 Andrew Dooris Prosthetic facet joint ligament
US6761720B1 (en) * 1999-10-15 2004-07-13 Spine Next Intervertebral implant
US6764491B2 (en) * 1999-10-21 2004-07-20 Sdgi Holdings, Inc. Devices and techniques for a posterior lateral disc space approach
US20040143264A1 (en) * 2002-08-23 2004-07-22 Mcafee Paul C. Metal-backed UHMWPE rod sleeve system preserving spinal motion
US6783527B2 (en) * 2001-10-30 2004-08-31 Sdgi Holdings, Inc. Flexible spinal stabilization system and method
US20050010291A1 (en) * 2003-07-08 2005-01-13 Archus Orthopedics Inc. Prostheses, tools and methods for replacement of natural facet joints with artificial facet joint surfaces
US20050049705A1 (en) * 2003-08-29 2005-03-03 Hale Horace Winston Facet implant
US6902566B2 (en) * 1997-01-02 2005-06-07 St. Francis Medical Technologies, Inc. Spinal implants, insertion instruments, and methods of use
US20050159746A1 (en) * 2004-01-21 2005-07-21 Dieter Grob Cervical facet resurfacing implant
US20050165484A1 (en) * 2004-01-22 2005-07-28 Ferree Bret A. Artificial disc replacement (ADR) fixation methods and apparatus
US6945973B2 (en) * 2003-05-01 2005-09-20 Nuvasive, Inc. Slidable bone plate system
US20060036243A1 (en) * 2004-08-13 2006-02-16 Ricardo Sasso Replacement facet joint and method
US20060142767A1 (en) * 2004-12-27 2006-06-29 Green Daniel W Orthopedic device and method for correcting angular bone deformity
US7101375B2 (en) * 1997-01-02 2006-09-05 St. Francis Medical Technologies, Inc. Spine distraction implant

Family Cites Families (197)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2456806A (en) 1947-01-14 1948-12-21 Erwin B Wolffe Vaginal gauge
US2677369A (en) 1952-03-26 1954-05-04 Fred L Knowles Apparatus for treatment of the spinal column
GB780652A (en) 1954-04-30 1957-08-07 Zimmer Orthopaedic Ltd Improvements in or relating to apparatus for use in spinal fixation
US3426364A (en) 1966-08-25 1969-02-11 Colorado State Univ Research F Prosthetic appliance for replacing one or more natural vertebrae
CH497891A (en) 1968-09-03 1970-10-31 Straumann Inst Ag Implant made of titanium or a titanium-based alloy, used for surgical bone treatment
US3648691A (en) 1970-02-24 1972-03-14 Univ Colorado State Res Found Method of applying vertebral appliance
CA1045752A (en) 1975-05-26 1979-01-09 Robert W. Jackson Prosthetic implant
CH613858A5 (en) 1977-04-22 1979-10-31 Straumann Inst Ag
CH628803A5 (en) 1978-05-12 1982-03-31 Sulzer Ag Implant insertable between adjacent vertebrae
US4231121A (en) 1979-07-05 1980-11-04 Wright Dow Corning Metacarpal-phalangeal prosthesis
PL124738B1 (en) 1980-04-15 1983-02-28 Politechnika Slaska Im Wincentego Pstrowskiego Implant for internal spine stabilization
US4369769A (en) 1980-06-13 1983-01-25 Edwards Charles C Spinal fixation device and method
GB2083754B (en) 1980-09-15 1984-04-26 Rezaian Seyed Mahmoud Spinal fixator
US4455690A (en) 1980-11-06 1984-06-26 Homsy Charles A Structure for in vivo implanation
US4309777A (en) 1980-11-13 1982-01-12 Patil Arun A Artificial intervertebral disc
US4501269A (en) 1981-12-11 1985-02-26 Washington State University Research Foundation, Inc. Process for fusing bone joints
US4479491A (en) 1982-07-26 1984-10-30 Martin Felix M Intervertebral stabilization implant
US4599084A (en) 1983-05-24 1986-07-08 American Hospital Supply Corp. Method of using biological tissue to promote even bone growth
US4554914A (en) 1983-10-04 1985-11-26 Kapp John P Prosthetic vertebral body
US4553273A (en) 1983-11-23 1985-11-19 Henry Ford Hospital Vertebral body prosthesis and spine stabilizing method
US4696290A (en) 1983-12-16 1987-09-29 Acromed Corporation Apparatus for straightening spinal columns
US4611582A (en) 1983-12-27 1986-09-16 Wisconsin Alumni Research Foundation Vertebral clamp
US4604995A (en) 1984-03-30 1986-08-12 Stephens David C Spinal stabilizer
US4643178A (en) 1984-04-23 1987-02-17 Fabco Medical Products, Inc. Surgical wire and method for the use thereof
FR2575059B1 (en) 1984-12-21 1988-11-10 Daher Youssef SHORING DEVICE FOR USE IN A VERTEBRAL PROSTHESIS
US4685447A (en) 1985-03-25 1987-08-11 Pmt Corporation Tissue expander system
US4636217A (en) 1985-04-23 1987-01-13 Regents Of The University Of Minnesota Anterior spinal implant
US4599086A (en) 1985-06-07 1986-07-08 Doty James R Spine stabilization device and method
US4743256A (en) 1985-10-04 1988-05-10 Brantigan John W Surgical prosthetic implant facilitating vertebral interbody fusion and method
US4834757A (en) 1987-01-22 1989-05-30 Brantigan John W Prosthetic implant
US4714469A (en) 1987-02-26 1987-12-22 Pfizer Hospital Products Group, Inc. Spinal implant
SU1484348A1 (en) 1987-03-04 1989-06-07 Белорусский научно-исследовательский институт травматологии и ортопедии Spinal column fixing device
US4790303A (en) 1987-03-11 1988-12-13 Acromed Corporation Apparatus and method for securing bone graft
US4913134A (en) 1987-07-24 1990-04-03 Biotechnology, Inc. Spinal fixation system
GB8718627D0 (en) 1987-08-06 1987-09-09 Showell A W Sugicraft Ltd Spinal implants
FR2623085B1 (en) 1987-11-16 1992-08-14 Breard Francis SURGICAL IMPLANT TO LIMIT THE RELATIVE MOVEMENT OF VERTEBRES
JPH01136655A (en) 1987-11-24 1989-05-29 Asahi Optical Co Ltd Movable type pyramid spacer
US4874389A (en) 1987-12-07 1989-10-17 Downey Ernest L Replacement disc
DE3809793A1 (en) 1988-03-23 1989-10-05 Link Waldemar Gmbh Co SURGICAL INSTRUMENT SET
US5484437A (en) 1988-06-13 1996-01-16 Michelson; Gary K. Apparatus and method of inserting spinal implants
US5015247A (en) 1988-06-13 1991-05-14 Michelson Gary K Threaded spinal implant
US5593409A (en) 1988-06-13 1997-01-14 Sofamor Danek Group, Inc. Interbody spinal fusion implants
US4961740B1 (en) 1988-10-17 1997-01-14 Surgical Dynamics Inc V-thread fusion cage and method of fusing a bone joint
GB8825909D0 (en) 1988-11-04 1988-12-07 Showell A W Sugicraft Ltd Pedicle engaging means
US5074864A (en) 1988-12-21 1991-12-24 Zimmer, Inc. Clamp assembly for use in a spinal system
US5084049A (en) 1989-02-08 1992-01-28 Acromed Corporation Transverse connector for spinal column corrective devices
US4969888A (en) 1989-02-09 1990-11-13 Arie Scholten Surgical protocol for fixation of osteoporotic bone using inflatable device
CA1318469C (en) 1989-02-15 1993-06-01 Acromed Corporation Artificial disc
US5458638A (en) 1989-07-06 1995-10-17 Spine-Tech, Inc. Non-threaded spinal implant
CA2015507C (en) 1989-07-06 1999-01-05 Stephen D. Kuslich Spinal implant
US4936848A (en) 1989-09-22 1990-06-26 Bagby George W Implant for vertebrae
US4932975A (en) 1989-10-16 1990-06-12 Vanderbilt University Vertebral prosthesis
US4923471A (en) 1989-10-17 1990-05-08 Timesh, Inc. Bone fracture reduction and fixation devices with identity tags
US5055104A (en) 1989-11-06 1991-10-08 Surgical Dynamics, Inc. Surgically implanting threaded fusion cages between adjacent low-back vertebrae by an anterior approach
US5059193A (en) 1989-11-20 1991-10-22 Spine-Tech, Inc. Expandable spinal implant and surgical method
US5105255A (en) 1990-01-10 1992-04-14 Hughes Aircraft Company MMIC die attach design for manufacturability
US5062850A (en) 1990-01-16 1991-11-05 University Of Florida Axially-fixed vertebral body prosthesis and method of fixation
US5059194A (en) 1990-02-12 1991-10-22 Michelson Gary K Cervical distractor
DE59100448D1 (en) 1990-04-20 1993-11-11 Sulzer Ag Implant, in particular intervertebral prosthesis.
DE4012622C1 (en) 1990-04-20 1991-07-18 Eska Medical Luebeck Medizintechnik Gmbh & Co, 2400 Luebeck, De Two-part metal vertebra implant - has parts locked by two toothed racks, pre-stressed by elastic cushion between both implant parts
US5360431A (en) 1990-04-26 1994-11-01 Cross Medical Products Transpedicular screw system and method of use
US5540689A (en) 1990-05-22 1996-07-30 Sanders; Albert E. Apparatus for securing a rod adjacent to a bone
US5088869A (en) 1991-01-24 1992-02-18 Greenslade Joe E Thread rolling screw
FR2672202B1 (en) 1991-02-05 1993-07-30 Safir BONE SURGICAL IMPLANT, ESPECIALLY FOR INTERVERTEBRAL STABILIZER.
US5123926A (en) 1991-02-22 1992-06-23 Madhavan Pisharodi Artificial spinal prosthesis
US5390683A (en) 1991-02-22 1995-02-21 Pisharodi; Madhavan Spinal implantation methods utilizing a middle expandable implant
US5192327A (en) 1991-03-22 1993-03-09 Brantigan John W Surgical prosthetic implant for vertebrae
US5577995A (en) 1991-06-13 1996-11-26 Grace L. Walker Spinal and soft tissue mobilizer
US5290312A (en) 1991-09-03 1994-03-01 Alphatec Artificial vertebral body
US5275601A (en) 1991-09-03 1994-01-04 Synthes (U.S.A) Self-locking resorbable screws and plates for internal fixation of bone fractures and tendon-to-bone attachment
FR2681525A1 (en) 1991-09-19 1993-03-26 Medical Op Device for flexible or semi-rigid stabilisation of the spine, in particular of the human spine, by a posterior route
US5180381A (en) 1991-09-24 1993-01-19 Aust Gilbert M Anterior lumbar/cervical bicortical compression plate
US5263953A (en) 1991-12-31 1993-11-23 Spine-Tech, Inc. Apparatus and system for fusing bone joints
US5167665A (en) 1991-12-31 1992-12-01 Mckinney William W Method of attaching objects to bone
US5258031A (en) 1992-01-06 1993-11-02 Danek Medical Intervertebral disk arthroplasty
US5167662A (en) 1992-01-24 1992-12-01 Zimmer, Inc. Temporary clamp and inserter for a posterior midline spinal clamp
NL9200612A (en) 1992-04-01 1993-11-01 Acromed Bv Device for correcting the shape and / or fixing the vertebral column of man.
DE59206917D1 (en) 1992-04-21 1996-09-19 Sulzer Medizinaltechnik Ag Artificial intervertebral disc body
US5304178A (en) 1992-05-29 1994-04-19 Acromed Corporation Sublaminar wire
FR2693364B1 (en) 1992-07-07 1995-06-30 Erpios Snc INTERVERTEBRAL PROSTHESIS FOR STABILIZING ROTATORY AND FLEXIBLE-EXTENSION CONSTRAINTS.
GB9217578D0 (en) 1992-08-19 1992-09-30 Surgicarft Ltd Surgical implants,etc
JPH06178787A (en) 1992-12-14 1994-06-28 Shima Yumiko Centrum spacer with joint, intervertebral cavity measuring device and centrum spacer pattern
US5540703A (en) 1993-01-06 1996-07-30 Smith & Nephew Richards Inc. Knotted cable attachment apparatus formed of braided polymeric fibers
US5456722A (en) 1993-01-06 1995-10-10 Smith & Nephew Richards Inc. Load bearing polymeric cable
US5496318A (en) 1993-01-08 1996-03-05 Advanced Spine Fixation Systems, Inc. Interspinous segmental spine fixation device
US5352225A (en) 1993-01-14 1994-10-04 Yuan Hansen A Dual-tier spinal clamp locking and retrieving system
US6030162A (en) 1998-12-18 2000-02-29 Acumed, Inc. Axial tension screw
US5470333A (en) 1993-03-11 1995-11-28 Danek Medical, Inc. System for stabilizing the cervical and the lumbar region of the spine
US5531745A (en) 1993-03-11 1996-07-02 Danek Medical, Inc. System for stabilizing the spine and reducing spondylolisthesis
DE59308808D1 (en) 1993-03-15 1998-08-27 Synthes Ag HOOK WITH SCREW FOR TREATING SPINE DEFORMITY
DE9304368U1 (en) 1993-03-18 1993-05-13 Aap Gmbh & Co. Betriebs Kg, 1000 Berlin, De
FR2705227B1 (en) 1993-05-18 1995-07-28 Felman Daniel Inter-thorny implant with double metal shell.
FR2707480B1 (en) 1993-06-28 1995-10-20 Bisserie Michel Intervertebral disc prosthesis.
FR2707864B1 (en) 1993-07-23 1996-07-19 Jean Taylor Surgical forceps for tensioning an osteosynthesis ligament.
US5395372A (en) 1993-09-07 1995-03-07 Danek Medical, Inc. Spinal strut graft holding staple
US5458641A (en) 1993-09-08 1995-10-17 Ramirez Jimenez; Juan J. Vertebral body prosthesis
BE1007549A3 (en) 1993-09-21 1995-08-01 Beckers Louis Francois Charles Implant.
US5443514A (en) 1993-10-01 1995-08-22 Acromed Corporation Method for using spinal implants
CN1156255C (en) 1993-10-01 2004-07-07 美商-艾克罗米德公司 Spinal implant
US5454812A (en) 1993-11-12 1995-10-03 Lin; Chih-I Spinal clamping device having multiple distance adjusting strands
US5468242A (en) 1993-11-19 1995-11-21 Leibinger Gmbh Form-fitting mesh implant
US5507745A (en) 1994-02-18 1996-04-16 Sofamor, S.N.C. Occipito-cervical osteosynthesis instrumentation
FR2717066B1 (en) 1994-03-08 1996-05-15 Jean Taylor Bone implant especially for vertebrae pedicle.
FR2717068B1 (en) 1994-03-14 1996-04-26 Biomat Vertebral interbody fusion cage.
EP0677277A3 (en) 1994-03-18 1996-02-28 Patrice Moreau Spinal prosthetic assembly.
US6093207A (en) 1994-03-18 2000-07-25 Pisharodi; Madhavan Middle expanded, removable intervertebral disk stabilizer disk
DE4409833A1 (en) 1994-03-22 1995-10-05 Biedermann Motech Gmbh Stabilizing device, in particular for stabilizing the spine
FR2717675B1 (en) 1994-03-24 1996-05-03 Jean Taylor Interspinous wedge.
DE4414781C2 (en) 1994-04-28 2000-05-11 Schaefer Micomed Gmbh Bone surgery holding device
FR2719763B1 (en) 1994-05-11 1996-09-27 Jean Taylor Vertebral implant.
US5571189A (en) 1994-05-20 1996-11-05 Kuslich; Stephen D. Expandable fabric implant for stabilizing the spinal motion segment
FR2721501B1 (en) 1994-06-24 1996-08-23 Fairant Paulette Prostheses of the vertebral articular facets.
JP3107707B2 (en) 1994-06-29 2000-11-13 トヨタ自動車株式会社 Control method of pressure pin
FR2722088B1 (en) 1994-07-08 1998-01-23 Cahlik Marc Andre SURGICAL IMPLANT FOR STABILIZING THE INTERVERTEBRAL SPACE
US5616142A (en) 1994-07-20 1997-04-01 Yuan; Hansen A. Vertebral auxiliary fixation device
EP0700671B1 (en) 1994-09-08 2001-08-08 Stryker Technologies Corporation Hydrogel intervertebral disc nucleus
US5885299A (en) 1994-09-15 1999-03-23 Surgical Dynamics, Inc. Apparatus and method for implant insertion
FR2724554B1 (en) 1994-09-16 1997-01-24 Voydeville Gilles DEVICE FOR FIXING A LIGAMENT PROSTHESIS
US5601553A (en) 1994-10-03 1997-02-11 Synthes (U.S.A.) Locking plate and bone screw
US5562736A (en) 1994-10-17 1996-10-08 Raymedica, Inc. Method for surgical implantation of a prosthetic spinal disc nucleus
US5824098A (en) 1994-10-24 1998-10-20 Stein; Daniel Patello-femoral joint replacement device and method
FR2728159B1 (en) 1994-12-16 1997-06-27 Tornier Sa ELASTIC DISC PROSTHESIS
US5766252A (en) 1995-01-24 1998-06-16 Osteonics Corp. Interbody spinal prosthetic implant and method
US6206922B1 (en) 1995-03-27 2001-03-27 Sdgi Holdings, Inc. Methods and instruments for interbody fusion
US5520690A (en) 1995-04-13 1996-05-28 Errico; Joseph P. Anterior spinal polyaxial locking screw plate assembly
GB2306653B (en) 1995-10-23 1999-12-15 Finsbury Surgical tool
US6558686B1 (en) 1995-11-08 2003-05-06 Baylor College Of Medicine Method of coating medical devices with a combination of antiseptics and antiseptic coating therefor
US5899906A (en) 1996-01-18 1999-05-04 Synthes (U.S.A.) Threaded washer
US5672177A (en) 1996-01-31 1997-09-30 The General Hospital Corporation Implantable bone distraction device
US5658286A (en) 1996-02-05 1997-08-19 Sava; Garard A. Fabrication of implantable bone fixation elements
US5702455A (en) 1996-07-03 1997-12-30 Saggar; Rahul Expandable prosthesis for spinal fusion
US6228900B1 (en) 1996-07-09 2001-05-08 The Orthopaedic Hospital And University Of Southern California Crosslinking of polyethylene for low wear using radiation and thermal treatments
US6045554A (en) 1996-07-16 2000-04-04 University Of Florida Tissue Bank, Inc. Cortical bone interference screw
US6190414B1 (en) 1996-10-31 2001-02-20 Surgical Dynamics Inc. Apparatus for fusion of adjacent bone structures
US5836948A (en) 1997-01-02 1998-11-17 Saint Francis Medical Technologies, Llc Spine distraction implant and method
DE69839498D1 (en) 1997-02-11 2008-06-26 Warsaw Orthopedic Inc Plate for the anterior cervical spine with fixation system for one screw
US6139550A (en) 1997-02-11 2000-10-31 Michelson; Gary K. Skeletal plating system
ZA983955B (en) 1997-05-15 2001-08-13 Sdgi Holdings Inc Anterior cervical plating system.
US6022376A (en) 1997-06-06 2000-02-08 Raymedica, Inc. Percutaneous prosthetic spinal disc nucleus and method of manufacture
US6007538A (en) 1997-07-25 1999-12-28 Duke University Sternal closure device
FR2766353B1 (en) 1997-07-28 1999-11-26 Dimso Sa IMPLANT, ESPECIALLY ANTERIOR CERVICAL PLATE
FR2770767B1 (en) 1997-11-10 2000-03-10 Dimso Sa IMPLANT FOR VERTEBRA
US5888226A (en) 1997-11-12 1999-03-30 Rogozinski; Chaim Intervertebral prosthetic disc
US6048204A (en) 1998-02-03 2000-04-11 Lifecore Biomedical, Inc. Self tapping screw type dental implant
US6132465A (en) 1998-06-04 2000-10-17 Raymedica, Inc. Tapered prosthetic spinal disc nucleus
US6250308B1 (en) 1998-06-16 2001-06-26 Cardiac Concepts, Inc. Mitral valve annuloplasty ring and method of implanting
WO1999065412A1 (en) 1998-06-18 1999-12-23 Pioneer Laboratories, Inc. Spinal fixation system
FR2780269B1 (en) 1998-06-26 2003-10-17 Euros Sa RACHIDIAN IMPLANT
FR2782911B1 (en) 1998-09-07 2000-11-24 Euros Sa SPINAL IMPLANT WITH MEANS FOR ATTACHING A VERTEBRUS AND A DEVICE FOR THE CROSS-LINKAGE OF TWO LONGITUDINAL RODS
US6352537B1 (en) 1998-09-17 2002-03-05 Electro-Biology, Inc. Method and apparatus for spinal fixation
EP1117335B1 (en) 1998-10-02 2009-03-25 Synthes GmbH Spinal disc space distractor
US6312443B1 (en) 1998-12-23 2001-11-06 Nuvasive, Inc. Expandable cannula
EP1217961B1 (en) 1999-01-25 2010-04-21 Warsaw Orthopedic, Inc. Instrument for creating an intervertebral space for receiving an implant
US6129730A (en) 1999-02-10 2000-10-10 Depuy Acromed, Inc. Bi-fed offset pitch bone screw
US6470207B1 (en) 1999-03-23 2002-10-22 Surgical Navigation Technologies, Inc. Navigational guidance via computer-assisted fluoroscopic imaging
US6113639A (en) 1999-03-23 2000-09-05 Raymedica, Inc. Trial implant and trial implant kit for evaluating an intradiscal space
US6234705B1 (en) 1999-04-06 2001-05-22 Synthes (Usa) Transconnector for coupling spinal rods
US7094239B1 (en) 1999-05-05 2006-08-22 Sdgi Holdings, Inc. Screws of cortical bone and method of manufacture thereof
CA2363562C (en) 1999-05-05 2010-08-03 Gary Karlin Michelson Nested interbody spinal fusion implants
US6558423B1 (en) 1999-05-05 2003-05-06 Gary K. Michelson Interbody spinal fusion implants with multi-lock for locking opposed screws
US6224602B1 (en) 1999-10-11 2001-05-01 Interpore Cross International Bone stabilization plate with a secured-locking mechanism for cervical fixation
US6811567B2 (en) 1999-10-22 2004-11-02 Archus Orthopedics Inc. Facet arthroplasty devices and methods
US6974478B2 (en) 1999-10-22 2005-12-13 Archus Orthopedics, Inc. Prostheses, systems and methods for replacement of natural facet joints with artificial facet joint surfaces
US20020133155A1 (en) 2000-02-25 2002-09-19 Ferree Bret A. Cross-coupled vertebral stabilizers incorporating spinal motion restriction
FR2806614B1 (en) 2000-03-21 2002-05-31 Cousin Biotech FASTENING DEVICE ON THE SACRUM
FR2806616B1 (en) 2000-03-21 2003-04-11 Cousin Biotech INTERPINEUSE SHIM AND FASTENING DEVICE ON THE SACRUM
US6436145B1 (en) 2000-06-02 2002-08-20 Zimmer, Inc. Plug for a modular orthopaedic implant and method for assembly
AU2001273356A1 (en) 2000-07-10 2002-01-21 Gary K. Michelson Flanged interbody spinal fusion implants
US6458131B1 (en) 2000-08-07 2002-10-01 Salut, Ltd. Apparatus and method for reducing spinal deformity
US6752831B2 (en) 2000-12-08 2004-06-22 Osteotech, Inc. Biocompatible osteogenic band for repair of spinal disorders
US6972019B2 (en) 2001-01-23 2005-12-06 Michelson Gary K Interbody spinal implant with trailing end adapted to receive bone screws
US6402756B1 (en) 2001-02-15 2002-06-11 Third Millennium Engineering, Llc Longitudinal plate assembly having an adjustable length
US7371238B2 (en) * 2001-02-16 2008-05-13 Queen's University At Kingston Method and device for treating scoliosis
US6565570B2 (en) 2001-03-14 2003-05-20 Electro-Biology, Inc. Bone plate and retractor assembly
US6368351B1 (en) 2001-03-27 2002-04-09 Bradley J. Glenn Intervertebral space implant for use in spinal fusion procedures
US7186256B2 (en) 2001-06-04 2007-03-06 Warsaw Orthopedic, Inc. Dynamic, modular, single-lock anterior cervical plate system having assembleable and movable segments
US7097645B2 (en) 2001-06-04 2006-08-29 Sdgi Holdings, Inc. Dynamic single-lock anterior cervical plate system having non-detachably fastened and moveable segments
US7041105B2 (en) 2001-06-06 2006-05-09 Sdgi Holdings, Inc. Dynamic, modular, multilock anterior cervical plate system having detachably fastened assembleable and moveable segments
US7044952B2 (en) 2001-06-06 2006-05-16 Sdgi Holdings, Inc. Dynamic multilock anterior cervical plate system having non-detachably fastened and moveable segments
US20030040746A1 (en) 2001-07-20 2003-02-27 Mitchell Margaret E. Spinal stabilization system and method
DE10135771B4 (en) 2001-07-23 2006-02-16 Aesculap Ag & Co. Kg Facet joint implant
US6669729B2 (en) 2002-03-08 2003-12-30 Kingsley Richard Chin Apparatus and method for the replacement of posterior vertebral elements
US20040087948A1 (en) 2002-08-29 2004-05-06 Loubert Suddaby Spinal facet fixation device
US6712852B1 (en) 2002-09-30 2004-03-30 Depuy Spine, Inc. Laminoplasty cage
US7608094B2 (en) 2002-10-10 2009-10-27 U.S. Spinal Technologies, Llc Percutaneous facet fixation system
EP1562498A4 (en) 2002-10-10 2008-11-19 Mekanika Inc Apparatus and method for restoring biomechanical function to a motion segment unit of the spine
US7063725B2 (en) 2002-10-21 2006-06-20 Sdgi Holdings, Inc. Systems and techniques for restoring and maintaining intervertebral anatomy
US7223269B2 (en) 2002-12-02 2007-05-29 Chappuis James L Facet fusion system
WO2004071358A1 (en) 2003-02-06 2004-08-26 Archus Orthopedics Inc. Facet arthroplasty devices and methods
US6908484B2 (en) 2003-03-06 2005-06-21 Spinecore, Inc. Cervical disc replacement
US7588589B2 (en) 2003-03-20 2009-09-15 Medical Designs Llc Posterior spinal reconstruction system
US7025789B2 (en) 2003-04-29 2006-04-11 The University Of Hong Kong Prosthetic device and method for total joint replacement in small joint arthroplasty
AU2003228821B2 (en) 2003-05-02 2009-07-16 Medicinelodge, Inc. Method and apparatus for spine joint replacement
US20040230304A1 (en) 2003-05-14 2004-11-18 Archus Orthopedics Inc. Prostheses, tools and methods for replacement of natural facet joints with artifical facet joint surfaces
US20040230201A1 (en) 2003-05-14 2004-11-18 Archus Orthopedics Inc. Prostheses, tools and methods for replacement of natural facet joints with artifical facet joint surfaces
US7051451B2 (en) 2004-04-22 2006-05-30 Archus Orthopedics, Inc. Facet joint prosthesis measurement and implant tools
US20060111780A1 (en) * 2004-11-22 2006-05-25 Orthopedic Development Corporation Minimally invasive facet joint hemi-arthroplasty

Patent Citations (100)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3867728A (en) * 1971-12-30 1975-02-25 Cutter Lab Prosthesis for spinal repair
US3879767A (en) * 1972-01-26 1975-04-29 Cutter Lab Prosthesis for articulating body structures
US3875595A (en) * 1974-04-15 1975-04-08 Edward C Froning Intervertebral disc prosthesis and instruments for locating same
US4085466A (en) * 1974-11-18 1978-04-25 National Research Development Corporation Prosthetic joint device
US4001896A (en) * 1975-06-09 1977-01-11 Zimmer, U.S.A. Inc. Prosthetic joint for total knee replacement
US4156296A (en) * 1977-04-08 1979-05-29 Bio-Dynamics, Inc. Great (large) toe prosthesis and method of implanting
US4349921A (en) * 1980-06-13 1982-09-21 Kuntz J David Intervertebral disc prosthesis
US4502161A (en) * 1981-09-21 1985-03-05 Wall W H Prosthetic meniscus for the repair of joints
US4502161B1 (en) * 1981-09-21 1989-07-25
US4759769A (en) * 1987-02-12 1988-07-26 Health & Research Services Inc. Artificial spinal disc
US4863477A (en) * 1987-05-12 1989-09-05 Monson Gary L Synthetic intervertebral disc prosthesis
US4904260A (en) * 1987-08-20 1990-02-27 Cedar Surgical, Inc. Prosthetic disc containing therapeutic material
US4772287A (en) * 1987-08-20 1988-09-20 Cedar Surgical, Inc. Prosthetic disc and method of implanting
US5147404A (en) * 1987-12-07 1992-09-15 Downey Ernest L Vertebra prosthesis
US4911718A (en) * 1988-06-10 1990-03-27 University Of Medicine & Dentistry Of N.J. Functional and biocompatible intervertebral disc spacer
US5545229A (en) * 1988-08-18 1996-08-13 University Of Medicine And Dentistry Of Nj Functional and biocompatible intervertebral disc spacer containing elastomeric material of varying hardness
USRE36221E (en) * 1989-02-03 1999-06-01 Breard; Francis Henri Flexible inter-vertebral stabilizer as well as process and apparatus for determining or verifying its tension before installation on the spinal column
US5092866A (en) * 1989-02-03 1992-03-03 Breard Francis H Flexible inter-vertebral stabilizer as well as process and apparatus for determining or verifying its tension before installation on the spinal column
US5445639A (en) * 1989-05-10 1995-08-29 Spine-Tech, Inc. Intervertebral reamer construction
US5015255A (en) * 1989-05-10 1991-05-14 Spine-Tech, Inc. Spinal stabilization method
US5306308A (en) * 1989-10-23 1994-04-26 Ulrich Gross Intervertebral implant
US5127912A (en) * 1990-10-05 1992-07-07 R. Charles Ray Sacral implant system
US5300073A (en) * 1990-10-05 1994-04-05 Salut, Ltd. Sacral implant system
US5192326A (en) * 1990-12-21 1993-03-09 Pfizer Hospital Products Group, Inc. Hydrogel bead intervertebral disc nucleus
US5047055A (en) * 1990-12-21 1991-09-10 Pfizer Hospital Products Group, Inc. Hydrogel intervertebral disc nucleus
US5458643A (en) * 1991-03-29 1995-10-17 Kyocera Corporation Artificial intervertebral disc
US5603713A (en) * 1991-09-24 1997-02-18 Aust; Gilbert M. Anterior lumbar/cervical bicortical compression plate
US5425773A (en) * 1992-01-06 1995-06-20 Danek Medical, Inc. Intervertebral disk arthroplasty device
US5562738A (en) * 1992-01-06 1996-10-08 Danek Medical, Inc. Intervertebral disk arthroplasty device
US5401269A (en) * 1992-03-13 1995-03-28 Waldemar Link Gmbh & Co. Intervertebral disc endoprosthesis
US5766251A (en) * 1992-03-13 1998-06-16 Tomihisa Koshino Wedge-shaped spacer for correction of deformed extremities
US5556431A (en) * 1992-03-13 1996-09-17 B+E,Uml U+Ee Ttner-Janz; Karin Intervertebral disc endoprosthesis
US5306309A (en) * 1992-05-04 1994-04-26 Calcitek, Inc. Spinal disk implant and implantation kit
US5591165A (en) * 1992-11-09 1997-01-07 Sofamor, S.N.C. Apparatus and method for spinal fixation and correction of spinal deformities
US5437672A (en) * 1992-11-12 1995-08-01 Alleyne; Neville Spinal cord protection device
US5868745A (en) * 1992-11-12 1999-02-09 Alleyne; Neville Spinal protection device
US5306275A (en) * 1992-12-31 1994-04-26 Bryan Donald W Lumbar spine fixation apparatus and method
US5527314A (en) * 1993-01-04 1996-06-18 Danek Medical, Inc. Spinal fixation system
US5676701A (en) * 1993-01-14 1997-10-14 Smith & Nephew, Inc. Low wear artificial spinal disc
US5534030A (en) * 1993-02-09 1996-07-09 Acromed Corporation Spine disc
US5415661A (en) * 1993-03-24 1995-05-16 University Of Miami Implantable spinal assist device
US5534028A (en) * 1993-04-20 1996-07-09 Howmedica, Inc. Hydrogel intervertebral disc nucleus with diminished lateral bulging
US5507823A (en) * 1993-12-28 1996-04-16 Walston; D. Kenneth Joint prosthesis having PTFE cushion
US5491882A (en) * 1993-12-28 1996-02-20 Walston; D. Kenneth Method of making joint prosthesis having PTFE cushion
US5879396A (en) * 1993-12-28 1999-03-09 Walston; D. Kenneth Joint prosthesis having PTFE cushion
US5514180A (en) * 1994-01-14 1996-05-07 Heggeness; Michael H. Prosthetic intervertebral devices
US5458642A (en) * 1994-01-18 1995-10-17 Beer; John C. Synthetic intervertebral disc
US5653762A (en) * 1994-03-18 1997-08-05 Pisharodi; Madhavan Method of stabilizing adjacent vertebrae with rotating, lockable, middle-expanded intervertebral disk stabilizer
US5645599A (en) * 1994-07-26 1997-07-08 Fixano Interspinal vertebral implant
US5527312A (en) * 1994-08-19 1996-06-18 Salut, Ltd. Facet screw anchor
US5674295A (en) * 1994-10-17 1997-10-07 Raymedica, Inc. Prosthetic spinal disc nucleus
US5824093A (en) * 1994-10-17 1998-10-20 Raymedica, Inc. Prosthetic spinal disc nucleus
US5674296A (en) * 1994-11-14 1997-10-07 Spinal Dynamics Corporation Human spinal disc prosthesis
US5865846A (en) * 1994-11-14 1999-02-02 Bryan; Vincent Human spinal disc prosthesis
USRE36758E (en) * 1995-03-16 2000-06-27 Fitz; William R. Artificial facet joint
US6080157A (en) * 1995-09-12 2000-06-27 Cg Surgical Limited Device to stabilize the lamina
US5716413A (en) * 1995-10-11 1998-02-10 Osteobiologics, Inc. Moldable, hand-shapable biodegradable implant material
US5645597A (en) * 1995-12-29 1997-07-08 Krapiva; Pavel I. Disc replacement method and apparatus
US5766253A (en) * 1996-01-16 1998-06-16 Surgical Dynamics, Inc. Spinal fusion device
US5951555A (en) * 1996-03-27 1999-09-14 Rehak; Lubos Device for the correction of spinal deformities
US5741261A (en) * 1996-06-25 1998-04-21 Sdgi Holdings, Inc. Minimally invasive spinal surgical methods and instruments
US6066325A (en) * 1996-08-27 2000-05-23 Fusion Medical Technologies, Inc. Fragmented polymeric compositions and methods for their use
US6902566B2 (en) * 1997-01-02 2005-06-07 St. Francis Medical Technologies, Inc. Spinal implants, insertion instruments, and methods of use
US5876404A (en) * 1997-01-02 1999-03-02 St. Francis Medical Technologies, Llc Spine distraction implant and method
US20020029039A1 (en) * 1997-01-02 2002-03-07 Zucherman James F. Supplemental spine fixation device and methods
US6048342A (en) * 1997-01-02 2000-04-11 St. Francis Medical Technologies, Inc. Spine distraction implant
US7101375B2 (en) * 1997-01-02 2006-09-05 St. Francis Medical Technologies, Inc. Spine distraction implant
US6068630A (en) * 1997-01-02 2000-05-30 St. Francis Medical Technologies, Inc. Spine distraction implant
US5893889A (en) * 1997-06-20 1999-04-13 Harrington; Michael Artificial disc
US5824094A (en) * 1997-10-17 1998-10-20 Acromed Corporation Spinal disc
US6014588A (en) * 1998-04-07 2000-01-11 Fitz; William R. Facet joint pain relief method and apparatus
US6019792A (en) * 1998-04-23 2000-02-01 Cauthen Research Group, Inc. Articulating spinal implant
US6063121A (en) * 1998-07-29 2000-05-16 Xavier; Ravi Vertebral body prosthesis
US6099531A (en) * 1998-08-20 2000-08-08 Bonutti; Peter M. Changing relationship between bones
US6113637A (en) * 1998-10-22 2000-09-05 Sofamor Danek Holdings, Inc. Artificial intervertebral joint permitting translational and rotational motion
US6039763A (en) * 1998-10-27 2000-03-21 Disc Replacement Technologies, Inc. Articulating spinal disc prosthesis
US20010018614A1 (en) * 1999-03-16 2001-08-30 Bianchi John R. Implants for orthopedic applications
US6200322B1 (en) * 1999-08-13 2001-03-13 Sdgi Holdings, Inc. Minimal exposure posterior spinal interbody instrumentation and technique
US6436101B1 (en) * 1999-10-13 2002-08-20 James S. Hamada Rasp for use in spine surgery
US6761720B1 (en) * 1999-10-15 2004-07-13 Spine Next Intervertebral implant
US6764491B2 (en) * 1999-10-21 2004-07-20 Sdgi Holdings, Inc. Devices and techniques for a posterior lateral disc space approach
US6610091B1 (en) * 1999-10-22 2003-08-26 Archus Orthopedics Inc. Facet arthroplasty devices and methods
US6293949B1 (en) * 2000-03-01 2001-09-25 Sdgi Holdings, Inc. Superelastic spinal stabilization system and method
US6579318B2 (en) * 2000-06-12 2003-06-17 Ortho Development Corporation Intervertebral spacer
US6579319B2 (en) * 2000-11-29 2003-06-17 Medicinelodge, Inc. Facet joint replacement
US20040116927A1 (en) * 2000-12-01 2004-06-17 Henry Graf Intervertebral stabilizing device
US6565605B2 (en) * 2000-12-13 2003-05-20 Medicinelodge, Inc. Multiple facet joint replacement
US6419703B1 (en) * 2001-03-01 2002-07-16 T. Wade Fallin Prosthesis for the replacement of a posterior element of a vertebra
US20030004572A1 (en) * 2001-03-02 2003-01-02 Goble E. Marlowe Method and apparatus for spine joint replacement
US6783527B2 (en) * 2001-10-30 2004-08-31 Sdgi Holdings, Inc. Flexible spinal stabilization system and method
US20040143264A1 (en) * 2002-08-23 2004-07-22 Mcafee Paul C. Metal-backed UHMWPE rod sleeve system preserving spinal motion
US20040059429A1 (en) * 2002-09-20 2004-03-25 Uri Amin Mechanically attached elastomeric cover for prosthesis
US20040127989A1 (en) * 2002-12-31 2004-07-01 Andrew Dooris Prosthetic facet joint ligament
US6945973B2 (en) * 2003-05-01 2005-09-20 Nuvasive, Inc. Slidable bone plate system
US20050010291A1 (en) * 2003-07-08 2005-01-13 Archus Orthopedics Inc. Prostheses, tools and methods for replacement of natural facet joints with artificial facet joint surfaces
US20050049705A1 (en) * 2003-08-29 2005-03-03 Hale Horace Winston Facet implant
US20050159746A1 (en) * 2004-01-21 2005-07-21 Dieter Grob Cervical facet resurfacing implant
US20050165484A1 (en) * 2004-01-22 2005-07-28 Ferree Bret A. Artificial disc replacement (ADR) fixation methods and apparatus
US20060036243A1 (en) * 2004-08-13 2006-02-16 Ricardo Sasso Replacement facet joint and method
US20060142767A1 (en) * 2004-12-27 2006-06-29 Green Daniel W Orthopedic device and method for correcting angular bone deformity

Cited By (119)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050261680A1 (en) * 2001-03-28 2005-11-24 Imperial College Innovations Ltd. Bone fixated, articulated joint load control device
US9610103B2 (en) 2001-03-28 2017-04-04 Moximed, Inc. Bone fixated, articulated joint load control device
US7763020B2 (en) 2001-03-28 2010-07-27 Moximed, Inc. Bone fixated, articulated joint load control device
US9943336B2 (en) 2001-03-28 2018-04-17 Moximed, Inc. Bone fixated, articulated joint load control device
US7998177B2 (en) 2004-02-17 2011-08-16 Gmedelaware 2 Llc Linked bilateral spinal facet implants and methods of use
US8906063B2 (en) 2004-02-17 2014-12-09 Gmedelaware 2 Llc Spinal facet joint implant
US7998178B2 (en) 2004-02-17 2011-08-16 Gmedelaware 2 Llc Linked bilateral spinal facet implants and methods of use
US7914560B2 (en) 2004-02-17 2011-03-29 Gmedelaware 2 Llc Spinal facet implant with spherical implant apposition surface and bone bed and methods of use
US7815648B2 (en) 2004-06-02 2010-10-19 Facet Solutions, Inc Surgical measurement systems and methods
US8777994B2 (en) 2004-06-02 2014-07-15 Gmedelaware 2 Llc System and method for multiple level facet joint arthroplasty and fusion
US11285010B2 (en) 2006-12-29 2022-03-29 Providence Medical Technology, Inc. Cervical distraction method
US9622873B2 (en) 2006-12-29 2017-04-18 Providence Medical Technology, Inc. Cervical distraction method
US7824431B2 (en) 2006-12-29 2010-11-02 Providence Medical Technology, Inc. Cervical distraction method
US8348979B2 (en) 2006-12-29 2013-01-08 Providence Medical Technology, Inc. Cervical distraction method
US20080208341A1 (en) * 2006-12-29 2008-08-28 Providence Medical Technology, Inc. Cervical distraction method
US10219910B2 (en) 2006-12-29 2019-03-05 Providence Medical Technology, Inc. Cervical distraction method
US8206418B2 (en) 2007-01-10 2012-06-26 Gmedelaware 2 Llc System and method for facet joint replacement with detachable coupler
US8252027B2 (en) 2007-01-10 2012-08-28 Gmedelaware 2 Llc System and method for facet joint replacement
US8211147B2 (en) 2007-01-10 2012-07-03 Gmedelaware 2 Llc System and method for facet joint replacement
US9050144B2 (en) 2007-04-17 2015-06-09 Gmedelaware 2 Llc System and method for implant anchorage with anti-rotation features
US8702759B2 (en) 2007-04-17 2014-04-22 Gmedelaware 2 Llc System and method for bone anchorage
US10639161B2 (en) 2007-05-01 2020-05-05 Moximed, Inc. Extra-articular implantable load sharing systems
US10070964B2 (en) 2007-05-01 2018-09-11 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems and implantation method
US8100967B2 (en) 2007-05-01 2012-01-24 Moximed, Inc. Adjustable absorber designs for implantable device
US8088166B2 (en) 2007-05-01 2012-01-03 Moximed, Inc. Adjustable absorber designs for implantable device
US10736746B2 (en) 2007-05-01 2020-08-11 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems
US11389298B2 (en) 2007-05-01 2022-07-19 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems
US9398957B2 (en) 2007-05-01 2016-07-26 Moximed, Inc. Femoral and tibial bases
US8409281B2 (en) 2007-05-01 2013-04-02 Moximed, Inc. Adjustable absorber designs for implantable device
US20080275559A1 (en) * 2007-05-01 2008-11-06 Exploramed Nc4, Inc. Adjustable absorber designs for implantable device
US10596007B2 (en) 2007-05-01 2020-03-24 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems and implantation method
US10383736B2 (en) 2007-05-01 2019-08-20 Moximed, Inc. Femoral and tibial base components
US20080275556A1 (en) * 2007-05-01 2008-11-06 Exploramed Nc4, Inc. Adjustable absorber designs for implantable device
US9655648B2 (en) 2007-05-01 2017-05-23 Moximed, Inc. Femoral and tibial base components
US7678147B2 (en) 2007-05-01 2010-03-16 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems and implantation method
US10327816B2 (en) 2007-05-01 2019-06-25 Moximed, Inc. Adjustable absorber designs for implantable device
US8709090B2 (en) 2007-05-01 2014-04-29 Moximed, Inc. Adjustable absorber designs for implantable device
US7655041B2 (en) 2007-05-01 2010-02-02 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems and implantation method
US8123805B2 (en) 2007-05-01 2012-02-28 Moximed, Inc. Adjustable absorber designs for implantable device
US9700419B2 (en) 2007-05-01 2017-07-11 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems and implantation method
US8801795B2 (en) 2007-05-01 2014-08-12 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems
US10022154B2 (en) 2007-05-01 2018-07-17 Moximed, Inc. Femoral and tibial base components
US8894714B2 (en) 2007-05-01 2014-11-25 Moximed, Inc. Unlinked implantable knee unloading device
US20080275565A1 (en) * 2007-05-01 2008-11-06 Exploramed Nc4, Inc. Adjustable absorber designs for implantable device
US10010421B2 (en) 2007-05-01 2018-07-03 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems
US9814579B2 (en) 2007-05-01 2017-11-14 Moximed, Inc. Unlinked implantable knee unloading device
US9005298B2 (en) 2007-05-01 2015-04-14 Moximed, Inc. Extra-articular implantable mechanical energy absorbing systems
US20080275557A1 (en) * 2007-05-01 2008-11-06 Exploramed Nc4, Inc. Adjustable absorber designs for implantable device
US20080275560A1 (en) * 2007-05-01 2008-11-06 Exploramed Nc4, Inc. Femoral and tibial base components
US9907645B2 (en) 2007-05-01 2018-03-06 Moximed, Inc. Adjustable absorber designs for implantable device
US9125746B2 (en) 2007-05-01 2015-09-08 Moximed, Inc. Methods of implanting extra-articular implantable mechanical energy absorbing systems
US9005288B2 (en) 2008-01-09 2015-04-14 Providence Medical Techonlogy, Inc. Methods and apparatus for accessing and treating the facet joint
US11559408B2 (en) 2008-01-09 2023-01-24 Providence Medical Technology, Inc. Methods and apparatus for accessing and treating the facet joint
US8696708B2 (en) 2008-03-06 2014-04-15 DePuy Synthes Products, LLC Facet interference screw
US9168065B2 (en) 2008-04-30 2015-10-27 Moximed, Inc. Ball and socket assembly
US20090276052A1 (en) * 2008-04-30 2009-11-05 Exploramed Nc4, Inc. Ball and socket assembly
US10363139B2 (en) 2008-04-30 2019-07-30 Moximed, Inc. Ball and socket assembly
US8425558B2 (en) 2008-06-06 2013-04-23 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US11141144B2 (en) 2008-06-06 2021-10-12 Providence Medical Technology, Inc. Facet joint implants and delivery tools
US9381049B2 (en) 2008-06-06 2016-07-05 Providence Medical Technology, Inc. Composite spinal facet implant with textured surfaces
US9333086B2 (en) 2008-06-06 2016-05-10 Providence Medical Technology, Inc. Spinal facet cage implant
US9622791B2 (en) 2008-06-06 2017-04-18 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US9629665B2 (en) 2008-06-06 2017-04-25 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US11890038B2 (en) 2008-06-06 2024-02-06 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US10238501B2 (en) 2008-06-06 2019-03-26 Providence Medical Technology, Inc. Cervical distraction/implant delivery device
US11344339B2 (en) 2008-06-06 2022-05-31 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US11272964B2 (en) 2008-06-06 2022-03-15 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US11224521B2 (en) 2008-06-06 2022-01-18 Providence Medical Technology, Inc. Cervical distraction/implant delivery device
US10226285B2 (en) 2008-06-06 2019-03-12 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US11058553B2 (en) 2008-06-06 2021-07-13 Providence Medical Technology, Inc. Spinal facet cage implant
US8267966B2 (en) 2008-06-06 2012-09-18 Providence Medical Technology, Inc. Facet joint implants and delivery tools
US8361152B2 (en) 2008-06-06 2013-01-29 Providence Medical Technology, Inc. Facet joint implants and delivery tools
US10588672B2 (en) 2008-06-06 2020-03-17 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US10568666B2 (en) 2008-06-06 2020-02-25 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US10039649B2 (en) 2008-06-06 2018-08-07 Providence Medical Technology, Inc. Composite spinal facet implant with textured surfaces
US10456175B2 (en) 2008-06-06 2019-10-29 Providence Medical Technology, Inc. Vertebral joint implants and delivery tools
US10149673B2 (en) 2008-06-06 2018-12-11 Providence Medical Technology, Inc. Facet joint implants and delivery tools
US10172721B2 (en) 2008-06-06 2019-01-08 Providence Technology, Inc. Spinal facet cage implant
US8512347B2 (en) 2008-06-06 2013-08-20 Providence Medical Technology, Inc. Cervical distraction/implant delivery device
US20100082065A1 (en) * 2008-10-01 2010-04-01 Butler Michael S Spinal Facet Fastener
US8715321B2 (en) * 2008-10-01 2014-05-06 Life Spine, Inc. Spinal facet fastener
US8845724B2 (en) 2009-08-27 2014-09-30 Cotera, Inc. Method and apparatus for altering biomechanics of the articular joints
US11517360B2 (en) 2009-08-27 2022-12-06 The Foundry, Llc Method and apparatus for treating canine cruciate ligament disease
US11730519B2 (en) 2009-08-27 2023-08-22 The Foundry, Llc Method and apparatus for force redistribution in articular joints
US10349980B2 (en) 2009-08-27 2019-07-16 The Foundry, Llc Method and apparatus for altering biomechanics of the shoulder
US8597362B2 (en) 2009-08-27 2013-12-03 Cotera, Inc. Method and apparatus for force redistribution in articular joints
US9668868B2 (en) 2009-08-27 2017-06-06 Cotera, Inc. Apparatus and methods for treatment of patellofemoral conditions
US20140156004A1 (en) * 2009-08-27 2014-06-05 Cotera, Inc. Method and Apparatus for Altering Biomechanics of the Articular Joints
US10695094B2 (en) 2009-08-27 2020-06-30 The Foundry, Llc Method and apparatus for altering biomechanics of articular joints
US9931136B2 (en) 2009-08-27 2018-04-03 The Foundry, Llc Method and apparatus for altering biomechanics of articular joints
US9278004B2 (en) 2009-08-27 2016-03-08 Cotera, Inc. Method and apparatus for altering biomechanics of the articular joints
US9795410B2 (en) 2009-08-27 2017-10-24 Cotera, Inc. Method and apparatus for force redistribution in articular joints
US9861408B2 (en) 2009-08-27 2018-01-09 The Foundry, Llc Method and apparatus for treating canine cruciate ligament disease
US9114016B2 (en) * 2009-08-27 2015-08-25 Cotera, Inc. Method and apparatus for altering biomechanics of the articular joints
US20110152932A1 (en) * 2009-12-21 2011-06-23 Industrial Technology Research Institute Flexible Spine Fixing Structure
US20110160771A1 (en) * 2009-12-31 2011-06-30 Industrial Technology Research Institute Flexible Spine Fixing Structure
US8702758B2 (en) 2009-12-31 2014-04-22 Industrial Technology Research Institute Flexible spine fixing structure
US8496688B2 (en) 2009-12-31 2013-07-30 Industrial Technology Research Institute Flexible spine fixing structure
US8986355B2 (en) 2010-07-09 2015-03-24 DePuy Synthes Products, LLC Facet fusion implant
US9044270B2 (en) 2011-03-29 2015-06-02 Moximed, Inc. Apparatus for controlling a load on a hip joint
US10898237B2 (en) 2012-08-24 2021-01-26 The Foundry, Llc Method and apparatus for altering biomechanics of the spine
US9468466B1 (en) 2012-08-24 2016-10-18 Cotera, Inc. Method and apparatus for altering biomechanics of the spine
USD745156S1 (en) 2012-10-23 2015-12-08 Providence Medical Technology, Inc. Spinal implant
USRE48501E1 (en) 2012-10-23 2021-04-06 Providence Medical Technology, Inc. Cage spinal implant
WO2015184012A3 (en) * 2014-05-27 2016-03-31 Providence Medical Technology, Inc. Lateral mass fixation implant
US11058466B2 (en) 2014-05-28 2021-07-13 Providence Medical Technology, Inc. Lateral mass fixation system
US10201375B2 (en) 2014-05-28 2019-02-12 Providence Medical Technology, Inc. Lateral mass fixation system
US10682243B2 (en) 2015-10-13 2020-06-16 Providence Medical Technology, Inc. Spinal joint implant delivery device and system
USD884895S1 (en) 2015-10-13 2020-05-19 Providence Medical Technology, Inc. Cervical cage
USD841165S1 (en) 2015-10-13 2019-02-19 Providence Medical Technology, Inc. Cervical cage
US11241256B2 (en) 2015-10-15 2022-02-08 The Foundry, Llc Method and apparatus for altering biomechanics of the shoulder
US11065039B2 (en) 2016-06-28 2021-07-20 Providence Medical Technology, Inc. Spinal implant and methods of using the same
USD887552S1 (en) 2016-07-01 2020-06-16 Providence Medical Technology, Inc. Cervical cage
US11871968B2 (en) 2017-05-19 2024-01-16 Providence Medical Technology, Inc. Spinal fixation access and delivery system
US11648128B2 (en) 2018-01-04 2023-05-16 Providence Medical Technology, Inc. Facet screw and delivery device
US11813172B2 (en) 2018-01-04 2023-11-14 Providence Medical Technology, Inc. Facet screw and delivery device
USD933230S1 (en) 2019-04-15 2021-10-12 Providence Medical Technology, Inc. Cervical cage
USD911525S1 (en) 2019-06-21 2021-02-23 Providence Medical Technology, Inc. Spinal cage
USD945621S1 (en) 2020-02-27 2022-03-08 Providence Medical Technology, Inc. Spinal cage

Also Published As

Publication number Publication date
US20110288556A1 (en) 2011-11-24
US8029540B2 (en) 2011-10-04
US20070016195A1 (en) 2007-01-18
US8425530B2 (en) 2013-04-23

Similar Documents

Publication Publication Date Title
US8029540B2 (en) Inter-cervical facet implant with implantation tool
US8100944B2 (en) Inter-cervical facet implant and method for preserving the tissues surrounding the facet joint
US20070016196A1 (en) Inter-cervical facet implant with implantation tool
US8172877B2 (en) Inter-cervical facet implant with surface enhancements
US7591851B2 (en) Inter-cervical facet implant and method
US8118838B2 (en) Inter-cervical facet implant with multiple direction articulation joint and method for implanting
AU2005316646B2 (en) Inter-facet implant
US8128660B2 (en) Inter-cervical facet joint implant with locking screw system
US20080177311A1 (en) Facet joint implant sizing tool
US8066749B2 (en) Implant for stabilizing a bone graft during spinal fusion
US11642230B2 (en) Expandable interspinous process fixation device
US7695513B2 (en) Distractible interspinous process implant and method of implantation
US20080177390A1 (en) Disk Replacement Endoprosthesis

Legal Events

Date Code Title Description
AS Assignment

Owner name: ST. FRANCIS MEDICAL TECHNOLOGIES, INC., CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WINSLOW, CHARLES J.;MITCHELL, STEVEN T.;MARKWART, JOHN A.;REEL/FRAME:018169/0329;SIGNING DATES FROM 20060712 TO 20060808

Owner name: ST. FRANCIS MEDICAL TECHNOLOGIES, INC., CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WINSLOW, CHARLES J.;MITCHELL, STEVEN T.;MARKWART, JOHN A.;SIGNING DATES FROM 20060712 TO 20060808;REEL/FRAME:018169/0329

AS Assignment

Owner name: BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT,WAS

Free format text: SECURITY AGREEMENT;ASSIGNOR:ST. FRANCIS MEDICAL TECHNOLOGIES, INC.;REEL/FRAME:018911/0427

Effective date: 20070118

Owner name: BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT, WA

Free format text: SECURITY AGREEMENT;ASSIGNOR:ST. FRANCIS MEDICAL TECHNOLOGIES, INC.;REEL/FRAME:018911/0427

Effective date: 20070118

AS Assignment

Owner name: KYPHON INC., CALIFORNIA

Free format text: MERGER;ASSIGNOR:ST. FRANCIS MEDICAL TECHNOLOGIES, INC.;REEL/FRAME:020393/0260

Effective date: 20071128

Owner name: KYPHON INC.,CALIFORNIA

Free format text: MERGER;ASSIGNOR:ST. FRANCIS MEDICAL TECHNOLOGIES, INC.;REEL/FRAME:020393/0260

Effective date: 20071128

AS Assignment

Owner name: KYPHON, INC., CALIFORNIA

Free format text: TERMINATION/RELEASE OF SECURITY INTEREST;ASSIGNOR:BANK OF AMERICA, N.A.;REEL/FRAME:020679/0107

Effective date: 20071101

Owner name: KYPHON, INC.,CALIFORNIA

Free format text: TERMINATION/RELEASE OF SECURITY INTEREST;ASSIGNOR:BANK OF AMERICA, N.A.;REEL/FRAME:020679/0107

Effective date: 20071101

AS Assignment

Owner name: MEDTRONIC SPINE LLC, CALIFORNIA

Free format text: CHANGE OF NAME;ASSIGNOR:KYPHON INC;REEL/FRAME:020993/0042

Effective date: 20080118

Owner name: MEDTRONIC SPINE LLC,CALIFORNIA

Free format text: CHANGE OF NAME;ASSIGNOR:KYPHON INC;REEL/FRAME:020993/0042

Effective date: 20080118

AS Assignment

Owner name: KYPHON SARL, SWITZERLAND

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MEDTRONIC SPINE LLC;REEL/FRAME:021070/0278

Effective date: 20080325

Owner name: KYPHON SARL,SWITZERLAND

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MEDTRONIC SPINE LLC;REEL/FRAME:021070/0278

Effective date: 20080325

STCF Information on status: patent grant

Free format text: PATENTED CASE

FPAY Fee payment

Year of fee payment: 4

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 8

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 12TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1553); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 12