Expandable implant, instrument, and method

Abstract

Embodiments of the invention include expandable, implantable devices and methods. Devices expand linearly to provide secure fixation between or among anatomical structures. In some embodiments, an implant replaces one or more vertebral bodies of the spine.

1 - 10 . (canceled) 
     
     
         11 . An expandable medical implant for supporting skeletal structures comprising:
 a first tubular member with a connection end and an opposite skeletal interface end;   a second tubular member with a connection end configured to engage with the connection end of the first tubular member, the second tubular member having an opposite skeletal interface end;   wherein the second tubular member intermittently locks relative to the first tubular member as the implant is expanded; and   an insertion instrument for translating the first tubular member relative to the second tubular member comprising:
 a first tip for attaching to the skeletal interface end of the first tubular member, 
 a second tip for attaching to the skeletal interface end of the second tubular member, and 
 a spreader mechanism for translating the first tip away from the second tip; 
   wherein moving the first tip toward the second tip results in the first tubular member being released relative to the second tubular member to permit the expandable medical implant to be reduced in length.   
     
     
         12 . The expandable medical implant of  claim 11  wherein the second tip includes a capture mechanism for engaging a portion of the implant that releases locking between the first and second tubular members. 
     
     
         13 . The expandable medical implant of  claim 12  wherein the capture mechanism connects the insertion instrument to the first and second tubular members to facilitate positioning or removal of the first and second tubular members. 
     
     
         14 . The expandable medical implant of  claim 11  wherein the first tip includes a capture mechanism for engaging a portion of the implant that releases locking between the first and second tubular members. 
     
     
         15 . The expandable medical implant of  claim 14  wherein the capture mechanism connects the insertion instrument to the first and second tubular members to facilitate positioning or removal of the first and second tubular members. 
     
     
         16 . The expandable medical implant of  claim 11  further comprising a set of two or more variously sized first interchangeable tips that may be placed one at a time on the insertion instrument in the position of the first tip to accommodate first tubular members of different, matching sizes. 
     
     
         17 . The expandable medical implant of  claim 11  further comprising a set of two or more variously sized second interchangeable tips that may be placed one at a time on the insertion instrument in the position of the second tip to accommodate second tubular members of different, matching sizes. 
     
     
         18 . An end member for a medical implant having a length, the end member configured to interface with a skeletal structure at the end of its length, comprising:
 an end cap with a thickness that provides connection to the medical implant and connection to the skeletal structure; and   a shoe for attachment to the end cap, the shoe spanning at least a portion of an opening through the end cap, and providing at least in part an interface with the skeletal structure.   
     
     
         19 . The end member of  claim 18  wherein the medical implant is a corpectomy device. 
     
     
         20 . The end member of  claim 18  wherein the end cap varies in thickness such that placement of the end member on the medical implant creates an interface with the implant that is not parallel to the length of the implant. 
     
     
         21 . The end member of  claim 20  wherein the end member and medical implant match the natural angles of a spinal curvature. 
     
     
         22 . The end member of  claim 21  wherein the angles of spinal curvature are lordotic angles. 
     
     
         23 . The end member of  claim 18  wherein the end cap includes surface irregularities to aid interface with the skeletal structure. 
     
     
         24 . The end member of  claim 23  wherein the surface irregularities are sharp spikes that penetrate the skeletal structure. 
     
     
         25 . The end member of  claim 18  wherein the end cap includes cap connectors for coupling the end cap to the medical implant. 
     
     
         26 . The end member of  claim 25  wherein the cap connectors are pins. 
     
     
         27 . The end member of  claim 25  wherein the medical implant includes an opening for receiving a cap connector, the opening having a cut from the opening through at least of portion of the surrounding material to provide a living hinge to securely receive the cap connector in the opening. 
     
     
         28 . The end member of  claim 18  wherein the shoe is convexly shaped relative to the end member. 
     
     
         29 . The end member of  claim 18  wherein the shoe is concavely shaped relative to the end member. 
     
     
         30 . The end member of  claim 18  wherein the shoe is at least in part a bioresorbable material. 
     
     
         31 - 37 . (canceled)