Systems and method in accordance with embodiments of the present invention can includes an implant having a spacer with an expandable portion. An insert can be positioned within a groove of the spacer to distract the expandable portion away from the main portion of the spacer. The expandable portion...http://www.google.de/patents/US8048117?utm_source=gb-gplus-sharePatent US8048117 - Interspinous process implant and method of implantation
