EXPANDABLE INTERVERTEBRAL IMPLANT AND ASSOCIATED SURGICAL METHOD

• US 20110172774A1
• Filed: 12/21/2010
• Published: 07/14/2011
• Est. Priority Date: 01/11/2010
• Status: Active Grant

• Current Assignee: Innova Spinal Technologies, LLC
• Original Assignee: Innova Spinal Technologies, LLC
• Inventors: VARELA, Armando
• Granted Patent: US 8,795,366 B2
• Time in Patent Office: Days
• US Class Current: 623/17.16
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/30281 wedge-shaped
• CPC Class Codes: A61F 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30522 releasable, e.g. using a releasable ratchet
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30556 for adjusting thickness
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts

Abstract

The present invention provides an expandable intervertebral implant that is selectively disposed in the intervertebral space and deployed, thereby in-situ distracting, realigning, and/or stabilizing or fusing a portion of the spine of a patient in the treatment of injury, disease, and/or degenerative condition. The expandable intervertebral implant includes a superior member and an inferior member, each of which has a partially or substantially wedge or prismatic shape and a partially or substantially convex or other-shaped surface that is suitable for engaging the substantially concave surfaces of the associated bony superior and inferior intervertebral endplates. Once disposed in the intervertebral space, the expandable intervertebral implant is actuated and deployed, with the superior member and the inferior member moving apart from one another, seating against the associated intervertebral endplates, and distracting, realigning, and/or stabilizing them to a desired degree. The external surface of each of the superior member and the inferior member is provided with a plurality of ridges or other friction structures, providing purchase with the associated intervertebral endplates.

Claims

1. An expandable intervertebral implant, comprising:

a superior member configured to engage a superior intervertebral body;

an inferior member configured to engage an inferior intervertebral body; and

an expansion mechanism disposed between the superior member and the inferior member configured to selectively adjust a separation of the superior member and the inferior member.

2. The expandable intervertebral implant of claim 1, wherein the expansion mechanism comprises a wedge structure that is translated between the superior member and the inferior member.

3. The expandable intervertebral implant of claim 2, wherein the expansion mechanism further comprises a screw that is coupled to the wedge structure and causes the wedge structure to translate when rotated.

4. The expandable intervertebral implant of claim 2, wherein one or more of the superior member and the inferior member comprise a ramp structure on their opposed faces.

5. The expandable intervertebral implant of claim 4, wherein interaction of the wedge structure and the ramp structure of the one or more of the superior member and the inferior member as the wedge structure is translated causes adjustment of the separation of the superior member and the inferior member.

6. The expandable intervertebral implant of claim 4, wherein the superior member is coupled to the inferior member through the wedge structure and the ramp structure of the one or more of the superior member and the inferior member.

7. The expandable intervertebral implant of claim 1, wherein the superior member is coupled to the inferior member via a track and rail system.

8. The expandable intervertebral implant of claim 1, wherein the expansion mechanism disposed between the superior member and the inferior member is also configured to selectively translate the superior member with respect to the inferior member.

9. An expandable intervertebral implant, comprising:

a superior member configured to engage a superior intervertebral body;

an inferior member configured to engage an inferior intervertebral body; and

an expansion mechanism disposed between the superior member and the inferior member configured to selectively adjust a separation of the superior member and the inferior member, wherein the expansion mechanism comprises a wedge structure that is translated between the superior member and the inferior member.

10. The expandable intervertebral implant of claim 9, wherein the expansion mechanism further comprises a screw that is coupled to the wedge structure and causes the wedge structure to translate when rotated.

11. The expandable intervertebral implant of claim 9, wherein one or more of the superior member and the inferior member comprise a ramp structure on their opposed faces.

12. The expandable intervertebral implant of claim 11, wherein interaction of the wedge structure and the ramp structure of the one or more of the superior member and the inferior member as the wedge structure is translated causes adjustment of the separation of the superior member and the inferior member.

13. The expandable intervertebral implant of claim 11, wherein the superior member is coupled to the inferior member through the wedge structure and the ramp structure of the one or more of the superior member and the inferior member.

14. The expandable intervertebral implant of claim 9, wherein the superior member is coupled to the inferior member via a track and rail system.

15. The expandable intervertebral implant of claim 9, wherein the expansion mechanism disposed between the superior member and the inferior member is also configured to selectively translate the superior member with respect to the inferior member.

16. A spinal surgical method, comprising:

providing an expandable intervertebral implant, comprising;

a superior member configured to engage a superior intervertebral body;

an inferior member configured to engage an inferior intervertebral body; and

an expansion mechanism disposed between the superior member and the inferior member configured to selectively adjust a separation of the superior member and the inferior member;

disposing the expandable intervertebral implant between the superior intervertebral body and the inferior intervertebral body; and

selectively adjusting the separation of the superior member and the inferior member, thereby selectively adjusting a distraction of the superior intervertebral body from the inferior intervertebral body.

17. The spinal surgical method of claim 16, wherein the expansion mechanism comprises a wedge structure that is translated between the superior member and the inferior member.

18. The spinal surgical method of claim 17, wherein the expansion mechanism further comprises a screw that is coupled to the wedge structure and causes the wedge structure to translate when rotated.

19. The spinal surgical method of claim 17, wherein one or more of the superior member and the inferior member comprise a ramp structure on their opposed faces.

20. The spinal surgical method of claim 19, wherein interaction of the wedge structure and the ramp structure of the one or more of the superior member and the inferior member as the wedge structure is translated causes adjustment of the separation of the superior member and the inferior member.

21. The spinal surgical method of claim 19, wherein the superior member is coupled to the inferior member through the wedge structure and the ramp structure of the one or more of the superior member and the inferior member.

22. The spinal surgical method of claim 16, wherein the superior member is coupled to the inferior member via a track and rail system.

23. The spinal surgical method of claim 16, wherein the expansion mechanism disposed between the superior member and the inferior member is also configured to selectively translate the superior member with respect to the inferior member.