WO1998011818A1

WO1998011818A1 - Speculum

Info

Publication number: WO1998011818A1
Application number: PCT/AU1997/000610
Authority: WO
Inventors: Alexandre Yorge Nunes Da Silva Pracas
Original assignee: Meditech International Pty. Ltd.
Priority date: 1996-09-18
Filing date: 1997-09-16
Publication date: 1998-03-26
Also published as: ZA978403B; AUPO244596A0

Abstract

A speculum (10) for insertion into a body cavity comprises a main body portion (12) and a plurality of dilator fingers (14A-14D). The main body (12) includes a collar (20) which is integrally formed with a handle (22). Fingers (14A-14D) are pivotally coupled by respective rearwardly extending hinges (18) to the collar (20). An actuator (16) is pivotally coupled to the handle (22) and has at a forward end a ring-like member (32) which passes through the collar (20) for movement inbetween and abutment with the dilator fingers (14). When actuator (16) is pivoted in a direction of insertion (I) of the speculum (10) into the body cavity, the ring member (32) abuts the inside surfaces of fingers (14) applying forces (TA-TD) in a direction transverse to the direction (I). This causes the fingers (14) to pivot away from each other thereby to dilate the body cavity. The further the actuator (16) is pushed in the direction of insertion (I), the greater the extension or pivoting of the fingers (14). The body cavity can be viewed and instrumented through the collar (20) and ring member (32).

Description

Title SPECULUM

Field of the Invention

The present invention is directed to a speculum for use in medical applications for dilating body cavities such as the vagina or the rectum.

Background of the Invention

A speculum is used for the dilation of the rectum or vagina to allow examination and/or instrumenting. A speculum typically includes two or more dilator blades or fingers which can be separated to push open the vaginal or rectal walls.

It is advantageous to allow single handed operation of the speculum co leave the other hand free for other purposes. When used for vaginal examination, it may be also advantageous for the manner or degree of movement of each blade or finger to differ. In particular, the uppermost finger of the speculum when held in its normal operating position should preferably separate further than the other blade members to allow a high degree of lifting of the anterior wall of the vagina which facilitates access to the cervix.

A speculum purporting to provide both of the above advantageous features is described in US patent no. 5509893. The speculum described in the specification uses a rotary cam to control the separation of the fingers. Each finger has a cam provided at a proximal end adjacent a handle of the speculum for engaging a rotary collar provided with camming surfaces. It is however believed that the described speculum does not achieve the above- mentioned advantages for the following reasons. The positioning of the cams at the end of each finger and the location of the pivot point of the finger near that end requires a high actuation force to separate the fingers. This is because the distance between the camming surfaces and the pivot point of the finger is only a small fraction of the distance between the distal end of the finger and the pivot point. There is therefore a poor leverage ratio when the fingers need to be separated. Furthermore, it is believed that any attempt to rotate the collar using one hand by means of a handle extending from the collar could result in the collar jamming. It would therefore still be necessary to use two hands to actuate the speculum.

A further apparent disadvantage of the speculum is that :: would seem that it could only accommodate uniforr. separation of the fingers. It is considered that the use of different camming surfaces to provide different degrees of movement of each blade as described in the patent may not be practical.

Additionally, the fingers are held loosely by the collar when not actuated. This may interfere with the insertion of the speculum.

The above-noted patent also discloses an embodiment of the speculum for use in rectal applications. It is however believed that the poor leverage ratio referred to above will adversely effect the performance of the speculum because of the generally higher dilation forces required.

Summary of the Invention

It is an object of the present invention to provide an improved speculum of simple construction which allows single handed operation. According to the present invention there is provided a speculum for insertion into a body cavity comprising: a main body portion; a plurality of dilator fingers each pivotally coupled at their respective proximal ends to said main body portion; and, an actuator supported on the main body portion in a manner so that when the actuator is pushed in the direction of insertion of the speculum into the body cavity, the actuator moves inbetween and abuts the dilator fingers applying force to each finger in the direction transverse to the direction of insertion to cause the fingers to pivot away from each other and thereby dilate the body cavity.

Preferably the fingers are biased toward each other so that in the absence of the transverse force applied by the actuator, the speculum is in a closed state with distal ends of the fingers adjacent each other.

Preferably the main body and dilator fingers are integrally formed as a single unit.

Preferably each finger is provided at its proximal end with an integral rearwardly extending hinge which is attached to the main body to facilitate the pivotal coupling of the fingers to the main body.

Preferably two of the fingers are diametrically opposed to each other and shaped at their respective distal ends so that together they form a duck-bill type structure when the speculum is in the closed state.

Preferably one of the two fingers is longer than the other of the two fingers. Preferably the main body comprises a collar to which the fingers are pivotally coupled by the hinges, and a handle to facilitate gripping and insertion of the speculum.

Preferably the actuator comprises abutment means for abuting an inside surface of the fingers when the actuator is pushed in the direction of insertion in order to apply said force in the transverse direction.

Preferably the abutment means comprises a tubular or ring like member through which the body cavity can be examined.

Preferably the abutment member and a first of the fingers are relatively configured so that the first finger commences to pivot before and/or pivots at a quicker rate than the other fingers when the actuator is pushed in the direction of insertion.

Preferably the actuator further comprises a lever pivotally coupled to the main body and a pair of spaced apart arms connecting the abutment means to the lever.

Preferably the speculum further comprises a releasable locking mechanism for locking the relative positions of the dilator fingers and subsequently releasing the fingers.

Preferably the releasable locking mechanism comprises a first component provided on the actuator and a second component provided on the main body, the first and second components arranged to engage each other when the actuator is pushed beyond an initial predetermined distance in the direction of insertion and adapted to release from each other when a force is applied to the actuator in a direction oblique to the direction of insertion.

Preferably the first component comprises one of a pawl and a rack of teeth like projections, and the second component comprises the other of the pawl and the rack, the pawl and rack being biased into engagement when the actuator is pushed beyond said predetermined distance in the direction of insertion, and being disengaged by application of said obliquely directed force to the pawl.

Preferably the pawl is provided on the lever of the actuator .

Preferably the actuator which comprises the abutment means, lever, arms, and pawl is integrally formed.

Preferably the lever is provided with a depression for receiving the thumb of an operator.

Preferably the depression is located near the pawl so that the actuator can be pushed in the direction of insertion and the pawl can be released from the rack of teeth by moving one's thumb a short distance from the depression to the pawl while maintaining a substantially constant grip on the handle.

Brief Description of the Drawings

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which:

Figure 1 is a perspective view from the front of an embodiment of the speculum;

Figure 2 is a perspective view from the rear of the speculum shown in Figure 1;

Figure 3 is a side view of the speculum;

Figure 4 is a top view of the speculum; Figure 5 is a front end view of the speculum; and,

Figure 6 is a sectional view of the speculum.

Referring to the accompanying drawings and in particular, Figures 2 and 6, it can be seen that a speculum 10 for insertion into a body cavity (not shown) comprises a main body portion 12 and a plurality of dilator fingers 14A-14D (hereinafter referred to generally as " finger (s) 14") . Each finger 14 is pivotally coupled at its proximal end to the main body portion 12. Actuator 16 is supported on the main body portion 12 in a manner so that when the actuator 16 is pushed in the direction of insertion of the speculum 10 into the body cavity (shown by arrow I) , the actuator 16 moves inbetween and abuts the dilator fingers 14 applying forces TA-TD (referred to in general as "forces T") to fingers 14A-14D respectively in a direction transverse to the direction of insertion. This causes the fingers 14 to pivot away from each other thereby dilating the body cavity.

Each finger 14 is attached to the main body 12 by a respective hinge 18. Each hinge 18 can be considered to be simply a rearward extension from the proximal end of each finger 14. The main body 12 and dilator fingers 14 (and thus also the hinges 18) are integrally formed as a single unit. The hinges 18 are arranged to bias the fingers 14 toward each other so that in the absence of the transverse forces T applied by the actuator 16, the speculum 10 is in a closed state with the ^'istal ends of the fingers 14 adjacent each other, as most clearly seen in Figure 5.

In the present embodiment, there are four fingers in total, with fingers 14B and 14D being diametrically opposed and of identical shape and configuration. When the speculum 10 is in its normal operating position inside a body cavity, the dilator fingers 14B and 14D would push against side walls of the body cavity.

Dilator fingers 14A and 14C are diametrically opposed from each other and interleaved between fingers 14B and 14D. When the speculum 10 is used for dilation of the vagina, and, is in its normal operating position, finger 14A would push against the anterior wall of the vagina.

As is apparent from Figures 1-4, and Figure 6, the respective distal ends of fingers 14A and 14C are shaped so that together they form a duck-bill like structure when the speculum 10 is in the closed state. However, the finger 14C is slightly longer than finger 14A.

Main body 12 comprises a collar 20 and integrally formed handle 22. The hinges 18 are equally spaced about forward edge 24 of the collar 20 and extend in the axial direction.

Handle 22 depends downwardly from the collar 20 at an angle substantially perpendicular to the direction of the length of the fingers 14. An end of the handle 22 distant the collar 20 is provided with an inwardly turned foot 26 against which the little finger of an operator can rest. The handle 22 has a generally U-shaped transverse section and comprises a front wall 28 and parallel spaced apart side walls 30 which extend rearwardly from longitudinal edges of the front wall 28.

Actuator 16 comprises abutment means in the form of a tubular or ring member 32 which abuts the inside surfaces of fingers 14 when the actuator 16 is pushed in direction I so as to apply forces T. As is most apparent from Figure 6, the ring member 32 passes through the collar 20 and, in this embodiment, abutments each of the fingers 14 simultaneously . The ring member 32 is supported at diametrically opposed locations by rearwardly extending beams 34. The opposite ends of the beams 34 are attached to bifurcated arm 36 via bifurcations 38. Arm 36 is pivotally coupled to the main body 12 at the foot 26 of handle 22, and shaped and configured so that when pushed in the direction of insertion I, it can fit between opposite side walls 30 of the handle 22.

The pivot connection of arm 36 to handle 22 can be achieved in any convenient mechanical form such as use of a separate pin which passes through the arm 36 and handle 22; or snap fit pins and detents formed on the arm 36 and handle 22. In a further embodiment, a web of material can be used to provide a hinge connection between the arm 36 and handle 22. This may be particularly advantageous as it would facilitate the manufacture of the speculum 10 as a single unit. In any event, the method of pivotally coupling the arm 36 to the main body 12 and handle 22 is of no significance to the present invention.

In order to maintain the fingers 14 at one of a sequence of predetermined positions, the speculum 10 is also provided with a releasable locking mechanism 40. The locking mechanism 40 comprises a first component in the form of a pawl 42 which is coupled to the actuator 16 via arm 36, and a rack of teeth 44 which is attached to the main body 12 via the handle 22.

The pawl 42 comprises a platform 46 which extends in the direction of the fingers 14 and is connected by downwardly depending spaced apart webs 48 to a cantilever 50. The cantilever 50 is formed as an upstanding tab on the arm 36.

On an underside of the platform 46 there is provided a hook or tooth 52. The rack 44 is formed as a rearward projection on the backside of wall 22 having on its upper surface a row of teeth 54.

When actuator 16 is pushed in the direction of insertion I, the arm 36 pivots toward handle 22 and the hook 52 will eventually come into contact with the rack 44 and the first of the teeth 54. The pawl 42 is configured so that when contact is made, the pawl 42 is biased into contact with the rack 44 thereby maintaining contact between the hook 52 and respective ones of the teeth 54. Therefore, if pressure is released from the actuator 22, the position of the arm 36 remains fixed and accordingly so is the position of the ring 32 between the fingers 14 thus maintaining the fingers 14 in a predetermined position. To release the fingers 14, force is applied to rearward end 56 of the pawl 42 in a direction oblique to direction I (ie. end 56 is pushed in a downward direction) which, as a result of the cantilever 50, results in a lifting of the hook 52 from the rack 44. The bias of the fingers together with the pressure of the body cavity acting on the fingers 14 then acts to collapse the fingers 14 back to the closed position.

To assist in the pushing or pivoting of actuator 16, a thumb depression 58 is formed on the arm 36. The thumb depression 58 is immediately below the pawl 42. In this way, the thumb of user can be moved easily between the thumb depression 58 and pawl 42 to spread and collapse the fingers 14.

The manner of use of the speculum 10 will now be described.

Initially, the speculum 10 in the closed state (ie. as shown in each of figures 1-6) is pushed into the body cavity by gripping the handle 22 only, or otherwise applying no substantial pressure on the arm 36. Once inserted, the thumb of the user is placed in thumb depression 58 and the actuator 16 is pushed in the direction of insertion I. This results in the arm 36 pivoting toward handle 22 and accordingly moving the ring 32 inbetween the fingers 14. As the outer surface of the ring 32 abuts the inside surfaces of the fingers 14, it applies forces T in the transverse direction causing fingers 14 to pivot about their respective hinges 18 in the direction of the force T, thereby dilating the body cavity. After a predetermined degree of pivoting of the arm 36 toward the handle 22, the pawl 42 will engage the rack 44. Because of the bias applied by pawl 42, once the hook 52 engages one of the teeth 54, the actuator 16 is prevented from moving in a direction opposite the direction of insertion I thereby effectively locking the actuator 16 in one of several predetermined positions. The further the actuator 16 is pushed in the direction I, the greater the extension or spreading of the fingers 14. In addition, as the actuator 16 is pushed further in the direction I, the hook 52 engages sequential ones of the teeth 54.

Once a desired dilation is achieved, the body cavity can be viewed through the collar 20 and ring member 32. Further, any instruments required for insertion into the body cavity can be inserted via the collar 20 and ring member 32.

In order to withdraw the speculum 10, the thumb of the user is moved from the depression 58 to the rearward end 56 of the pawl 42 and pulled down. This results in the hook 52 lifting upwardly releasing from the rack 44. This allows the actuator 16 to be moved in the direction opposite the direction of insertion I so that the fingers 14 can collapse toward the closed position under their own bias. When the closed position is achieved, the speculum 10 can be simply pulled out of the body cavity. Now that an embodiment of the present invention has been described in detail, it will be apparent to those skilled in the relevant arts that numerous modifications and variations may be made without departing from the basic inventive concepts. For example, the locking mechanism 40 comprising the pawl 42 and rack 44 can be dispensed with altogether. In such an embodiment, the operator would need to maintain pressure on the arm 36 to maintain a desired opening or dilation of the body cavity. Nevertheless, the other hand of the operator would still be free and could therefore be used for instrumenting the body cavity.

In addition, the actuator 16 and/or one of the fingers 14 can be arranged so that that finger can pivot either at a greater rate than the other fingers and/or commence pivoting prior to pivoting of the other fingers . One way of doing this would be to attach the ring member 32 at an acute angle to the beams 34 so that the ring member 32 abuts one of the fingers 14 prior to abutment with the other fingers. Alternately, the pivot point or hinge 18 of one of the fingers can be moved relative to that of the other fingers to effect the change in the relative timing of the commencement of pivoting of the fingers. As another alternative, a ramp may be provided on an inside surface of a particular finger and of a profile different to the profile of the inside surfaces of the other fingers so as to facilitate earlier and/or quicker pivoting when contacted by ring 32. In yet a further variation, the ring member 32 can be pivotally coupled to the beams 34.

In another embodiment, one or more of the fingers 14 can be fixedly coupled to the main body 12 so that it does not pivot. For example, finger 14C can be directly attached to the collar 20 without a hinge 18 so that it does not pivot.

Naturally, the speculum 10 can be provided with any number of fingers and the overall shape of the fingers when in the closed state can be different to that as shown in the accompanying drawings. For example, when the speculum 10 is used for rectal dilation, the fingers 14 are likely to be narrower and perhaps form a cone like structure when in the collapsed or closed state.

All such modifications and variations are deemed to be within the scope, of the present invention, the nature of which is to be determined from the foregoing description and the appended claims .

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:-

1. A speculum for insertion into a body cavity comprising: a main body portion; a plurality of dilator fingers each pivotally coupled at their respective proximal ends to said main body portion; and, an actuator supported on the main body portion in a manner so that when the actuator is pushed in the direction of insertion of the speculum into the body cavity, the actuator moves inbetween and abuts the dilator fingers applying force to each finger in the direction transverse to the direction of insertion to cause the fingers to pivot away from each other and thereby dilate the body cavity.

2. A speculum according to claim 1 wherein the actuator comprises abutment means for abuting an inside surface of the fingers when the actuator is pushed in the direction of insertion in order to apply said force in the transverse direction.

3. A speculum according to claim 2, wherein the abutment means comprises a tubular or ring like member through which the body cavity can be examined.

4. A speculum according to claim 3 , wherein the actuator further comprises a lever pivotally coupled to the main body and a pair of spaced apart arms connecting the abutment means to the lever.

5. A speculum according to claim 3, wherein the abutment member and a first of the fingers are relatively configured so that the first finger commences to pivot before and/or pivots at a quicker rate than the other fingers when the actuator is pushed in the direction of insertion.

6. A speculum according to claim 4, further comprising a releasable locking mechanism for locking the relative positions of the dilator fingers and subsequently releasing the fingers.

7. A speculum according to claim 6, wherein the releasable locking mechanism comprises a first component provided on the actuator and a second component provided on the main body, the first and second components arranged to engage each other when the actuator is pushed beyond an initial predetermined distance in the direction of insertion and adapted to release from each other when a force is applied to the actuator in a direction oblique to the direction of insertion.

8. A speculum according to claim 7, wherein the first component comprises one of a pawl and a rack of teeth like projections, and the second component comprises the other of the pawl and the rack, the pawl and rack being biased into engagement when the actuator is pushed beyond said predetermined distance in the direction of insertion, and being disengaged by application of said obliquely directed force to the pawl.

9. A speculum according to claim 8, wherein the pawl is provided on the lever of the actuator.

10. A speculum according to claim 9, wherein the actuator which comprises the abutment means, lever, arms, and pawl is integrally formed.

11. A speculum according to claim 10, wherein the lever is provided with a depression for receiving the thumb of an operator.

12. A speculum according to claim 11, wherein the depression is located near the pawl so that the actuator can be pushed in the direction of insertion and the pawl can be released from the rack of teeth by moving one's thumb a short distance from the depression to the pawl while maintaining a substantially constant grip on the handle .

13. A speculum according to claim 1, wherein the fingers are biased toward each other so that in the absence of the transverse force applied by the actuator, the speculum is in a closed state with distal ends of the fingers adjacent each other.

14. A speculum according to claim 13, wherein the main body and dilator fingers are integrally formed as a single unit.

15. A speculum according to claim 14, wherein each finger is provided at its proximal end with an integral rearwardly extending hinge which is attached to the main body to facilitate the pivotal coupling of the fingers to the main body.

16. A speculum according to claim 15, wherein two of the fingers are diametrically opposed to each other and shaped at their respective distal ends so that together they form a duck-bill type structure when the speculum is in the closed state.

17. A speculum according to claim 16, wherein one of the two fingers is longer than the other of the two fingers .

18. A speculum according to claim 15, wherein the main body comprises a collar to which the fingers are pivotally coupled by the hinges, and a handle to facilitate gripping and insertion of the speculum.