System and methods for spinal fusion

• US 8,187,334 B2
• Filed: 04/04/2011
• Issued: 05/29/2012
• 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): Robert, Eduardo C
• Assistant Examiner(s): Bray, Stuart S
• Application Number:
  US13/079,645
• Publication Number:
  US 20120029641A1
• Time in Patent Office: 421 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, said distal wall, proximal wall, first sidewall, and second sidewall comprising 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;

wherein a central region of said implant includes portions of the first and second sidewalls positioned generally centrally between the proximal wall and the distal wall, at least a portion of the central region defining a maximum lateral width of said implant extending from said first sidewall to said second sidewall, wherein said longitudinal length is at least two and half times greater than said maximum lateral width;

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 a lateral aperture width extending between said first sidewall to said second sidewall, wherein the longitudinal aperture length is greater than the lateral aperture width; and

at least three radiopaque markers;

wherein a first of the at least three radiopaque markers is at least partially positioned in said distal wall, a second of said at least three radiopaque markers is at least partially positioned in said proximal wall, and a third of said at least three radiopaque markers is at least partially positioned in said central region.

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 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 medial support extending between the first and second sidewalls.

7. The spinal fusion implant of claim 6, wherein said medial support is positioned along said central region.

8. 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.

9. The spinal fusion implant of claim 8, wherein said second fusion aperture is separated from said first fusion aperture by a medial support.

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

11. The spinal fusion implant of claim 10, wherein said plurality of ridges extend generally perpendicular to said longitudinal length.

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

13. The spinal fusion implant of claim 12, wherein said spike elements protrude to pointed tips configured to engage said first vertebra.

14. The spinal fusion implant of claim 1, wherein at least one of said three radiopaque markers comprises an elongate body extending generally perpendicular to said longitudinal length.

15. The spinal fusion implant of claim 14, wherein aid elongate body of at least one of said three radiopaque markers is shorter than a height extending from said upper surface to said lower surface.

16. The spinal fusion implant of claim 1, further comprising a fourth radiopaque marker situated within said implant, said fourth radiopaque marker positioned in said central region at a position spaced apart from said third radiopaque marker.

17. The spinal fusion implant of claim 1, wherein said first radiopaque marker has an elongate body oriented generally perpendicular to said longitudinal length and extending entirely through a height of said distal wall, and wherein said second radiopaque marker has an elongate body oriented generally perpendicular to said longitudinal length and entirely through a height of said proximal wall.

18. The spinal fusion implant of claim 1, wherein said maximum 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 spinal fusion implant of claim 1, wherein said maximum lateral width of said implant is greater than a lateral width of the distal end of said distal wall and is greater than a lateral width of the proximal end of said proximal wall.

25. The spinal fusion implant of claim 1, wherein said implant has a height extending from said upper surface to said lower surface, wherein said maximum lateral width is greater than said height.

26. The spinal fusion implant of claim 1, wherein said central region includes a maximum height of said implant extending from said upper surface to said lower surface, wherein said maximum height is greater than a height of said distal wall and is greater than a height of said proximal wall.

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

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