Systems and methods for spinal fusion

• US 8,246,686 B1
• Filed: 04/05/2012
• Issued: 08/21/2012
• Est. Priority Date: 03/29/2004
• Status: Active Grant

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Nuvasive Incorporated
• Inventors: Curran, Matthew, Peterson, Mark
• Primary Examiner(s): Stewart, Alvin
• Assistant Examiner(s): BRAY, STUART SAMUEL
• Application Number:
  US13/440,062
• Publication Number:
  US 20120215317A1
• Time in Patent Office: 138 Days
• Field of Search: 623 1711- 1716
• US Class Current: 623/17.16
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• 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 2002/30265 Flat parallelepipeds
• CPC Class Codes: A61F 2002/30266 wedge-shaped parallelepipeds
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30617 Visible markings for adjusting, locating or measuring
• CPC Class Codes: A61F 2002/3082 Grooves
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/3093 for promoting ingrowth of bone tissue
• CPC Class Codes: A61F 2002/4615 of spacers
• CPC Class Codes: A61F 2002/4629 connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes

Abstract

A system and method for spinal fusion comprising a spinal fusion implant of non-bone construction releasably coupled to an insertion instrument dimensioned to introduce the spinal fusion implant into any of a variety of spinal target sites.

Claims

1. A spinal fusion implant of non-bone construction positionable within an interbody space between a first vertebra and a second vertebra, said implant comprising:

an upper surface including anti-migration elements to contact said first vertebra when said implant is positioned within the interbody space, a lower surface including anti-migration elements to contact said second vertebra when said implant is positioned within the interbody space, a distal wall, a proximal wall, a first sidewall, and a second sidewall generally opposite from the first sidewall, wherein said distal wall, proximal wall, first sidewall, and second sidewall comprise a radiolucent material;

wherein said implant has a longitudinal length greater than 40 mm extending from a proximal end of said proximal wall to a distal end of said distal wall, an implant width extending from said first sidewall to said second sidewall, wherein said longitudinal length is at least two and half times greater than said implant width, and wherein said implant width is greater than a distal width of said distal wall and is greater than a proximal width of said proximal wall;

at least a first fusion aperture extending through said upper surface and lower surface and configured to permit bone growth between the first vertebra and the second vertebra when said implant is positioned within the interbody space, said first fusion aperture having;

a longitudinal aperture length extending generally parallel to the longitudinal length of said implant, and an aperture width extending between said first sidewall to said second sidewall, wherein the longitudinal aperture length is greater than the aperture width; and

at least a first radiopaque marker at least partially arranged in said radiolucent material of said implant, wherein said first radiopaque marker is positioned proximate to a medial plane of said implant that extends through portions of the first and second sidewalls positioned generally centrally between the proximal and distal ends.

2. The spinal fusion implant of claim 1, further including at least one receiving aperture position is said proximal wall.

3. The spinal fusion implant of claim 2, wherein said threaded receiving aperture is configured to releasably mate with an inserter tool.

4. The spinal fusion implant of claim 3, wherein said receiving aperture comprises a threaded receiving aperture extending into said proximal wall and having a central axis generally parallel to said longitudinal length of said implant.

5. The spinal fusion implant of claim 4, further comprising a pair of lateral grooves positioned in said proximal wall and extending laterally of said threaded receiving aperture.

6. The spinal fusion implant of claim 1, further comprising a second radiopaque marker that extends into said distal wall, and a third radiopaque marker that extends into said proximal wall.

7. The spinal fusion implant of claim 6, further comprising a fourth radiopaque marker having an elongate body oriented generally perpendicular to said longitudinal length of said implant, wherein said fourth radiopaque marker is positioned proximate to said medial plane at a position spaced apart from said first radiopaque marker.

8. The spinal fusion implant of claim 6, wherein said second radiopaque marker extends entirely through a height of said distal wall, and wherein said third radiopaque marker extends entirely through a height of said proximal wall.

9. The spinal fusion implant of claim 1, further comprising a medial support extending between the first and second sidewalls.

10. The spinal fusion implant of claim 9, wherein said medial support is positioned along said medial plane.

11. The spinal fusion implant of claim 1, further including a second fusion aperture extending through said upper surface and lower surface and configured to permit bone growth between the first vertebra and the second vertebra when said implant is positioned within the interbody space.

12. The spinal fusion implant of claim 11, wherein said second fusion aperture is separated from said first fusion aperture by a medial support.

13. The spinal fusion implant of claim 1, wherein said anti-migration elements of said upper surface comprise a plurality of ridges.

14. The spinal fusion implant of claim 13, wherein said plurality of ridges extend generally perpendicular to said longitudinal length.

15. The spinal fusion implant of claim 1, wherein said anti-migration elements of said upper surface comprise spike elements.

16. The spinal fusion implant of claim 15, wherein said spike elements protrude to pointed tips configured to engage said first vertebra.

17. The spinal fusion implant of claim 1, wherein a first longitudinal distance from the proximal end to the first radiopaque marker is substantially equal to a second longitudinal distance from the distal end to the first radiopaque marker.

18. The spinal fusion implant of claim 1, wherein said lateral width of said implant is approximately 18 mm.

19. The spinal fusion implant of claim 1, wherein said radiolucent material comprises PEEK.

20. The spinal fusion implant of claim 1, wherein said implant includes at least one visualization aperture extending through at least one of said first sidewall and said second sidewall.

21. The spinal fusion implant of claim 1, wherein said upper and lower surfaces are generally parallel to one another.

22. The spinal fusion implant of claim 1, wherein said upper and lower surfaces are generally angled relative to one another to approximately correspond to lordosis of a lumbar spine when said implant is positioned within the interbody space.

23. The spinal fusion implant of claim 1, wherein said first fusion aperture is one of generally rectangular and generally oblong in shape.

24. The implant of claim 1, wherein said implant has a height extending from said upper surface to said lower surface, wherein said implant width is greater than said height and wherein said first radiopaque marker comprises an elongate body oriented generally parallel to said height of said implant.

25. The spinal fusion implant of claim 24, wherein said elongate body of said first radiopaque markers is shorter than said height extending from said upper surface to said lower surface.

26. The implant of claim 1, wherein said implant width is proximate to said medial plane of said implant.

27. The spinal fusion implant of claim 1, wherein the aperture width of said first fusion aperture is more than two times greater than a thickness of said first sidewall extending generally parallel to the aperture width and is more than two time greater than a thickness of said second sidewall extending generally parallel to the aperture width.

28. The spinal fusion implant of claim 1, further comprising an osteoinductive material positioned with said first fusion aperture.

29. The spinal fusion implant of claim 1, wherein said implant is configured to be positioned within the interbody space via a lateral trans-psoas surgical approach between the first vertebra and the second vertebra.

30. The spinal fusion implant of claim 1, wherein said distal wall includes a tapered tip region to leadingly insert through a lateral aspect of said interbody space, said first sidewall is configured to face an anterior aspect of said interbody space when said implant is positioned within the interbody space, and said second sidewall is configured to face a posterior aspect of said interbody space when said implant is positioned within the interbody space.