Intervertebral implants and graft delivery systems and methods

• US 8,343,224 B2
• Filed: 03/16/2011
• Issued: 01/01/2013
• Est. Priority Date: 03/16/2010
• Status: Active Grant

• Current Assignee: Spine Holdings, LLC
• Original Assignee: Pinnacle Spine Group, LLC
• Inventors: Lynn, Jim R., Nelson, Russell W.
• Primary Examiner(s): Hammond, Ellen C
• Application Number:
  US13/049,693
• Publication Number:
  US 20110230970A1
• Time in Patent Office: 657 Days
• Field of Search: 623 1711- 1716, 606/246
• US Class Current: 623/17.16
• 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 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/46 Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
• CPC Class Codes: A61F 2/4601 for introducing bone substitute, for implanting bone graft implants or for compacting them in the bone cavity
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/3008 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/30281 wedge-shaped
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30754 Implants for interposition between two natural articular surfaces
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/4628 with linear motion along or rotating motion about an axis transverse to the instrument axis or to the implantation direction, e.g. clamping
• CPC Class Codes: A61F 2002/4629 connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2002/4631 the prosthesis being specially adapted for being cemented
• CPC Class Codes: A61F 2310/00011 Metals or alloys

Abstract

According to some embodiments, a method for promoting spinal fusion using a spinal implant comprises providing a spinal implant, wherein the spinal implant comprises an anterior wall, a posterior wall and two lateral walls configured to extend between the anterior wall and the posterior wall. In some embodiments, the spinal implant further comprises at least one internal chamber generally positioned between the anterior wall, the posterior wall and the two lateral walls, wherein the internal chamber being is adapted to receive at least one graft and/or other fill material. In some arrangements, the anterior wall of the spinal implant comprises at least one opening or hole that places the internal chamber in fluid communication with an exterior area or portion of the spinal implant. In one embodiment, at least one of the two lateral walls comprises an access port. The method additionally includes positioning the spinal implant between two adjacent vertebrae of a patient and directing at least one graft and/or other fill material into the internal chamber of the spinal implant through the access port. In some embodiments, at least a portion of the graft and/or other fill material delivered into the internal chamber is configured to exit through the one or more of the openings of the anterior wall.

Claims

1. A spinal implant configured for placement within an intervertebral space of a human subject, comprising:

an anterior wall and a posterior wall, said posterior wall being generally opposite of said anterior wall;

a first lateral wall and a second lateral wall extending between the anterior wall and the posterior wall;

at least one internal chamber defined, at least in part, by the anterior wall, the posterior wall and the first and second lateral walls;

a top surface comprising a plurality of teeth configured to engage a lower surface of a first vertebral body;

a bottom surface comprising a plurality of teeth configured to engage an upper surface of a second vertebral body, the second vertebral body being immediately adjacent to said first vertebral body;

wherein the at least one internal chamber extends at least partially from the top surface to the bottom surface of the implant;

at least one opening extending through the anterior wall, said at least one opening being in fluid communication with the at least one internal chamber;

at least one access port located in at least one of the anterior wall, the first lateral wall and the second lateral wall, wherein the implant is configured to releasably secure to an insertion tool at said at least one access port;

wherein the implant is sized and configured to span across an entire width of the first and second vertebral bodies of a mature adult human being;

wherein each of the first and second lateral walls is configured to generally align with peripheral bearing areas of the first and second vertebral bodies and to support adjacent cortical rims of the first and second vertebral bodies;

wherein the at least one access port is configured to provide a passage through which at least one graft material can be selectively delivered into the at least one internal chamber;

wherein the posterior wall does not comprise any openings;

wherein the posterior wall is generally planar to permit the implant to be inserted between the first and second vertebral bodies laterally; and

wherein a length of each of the first and second lateral walls is a minimum of 12% of an overall length of the implant.

2. The spinal implant of claim 1, wherein the at least one opening of the anterior wall is configured to provide a passage for graft material.

3. The spinal implant of claim 1, wherein the access port is threaded, so that a delivery tool comprising a corresponding thread pattern can be selectively attached to and detached from the spinal implant.

4. The spinal implant of claim 1, wherein the plurality of teeth along the top and bottom surfaces of the implant slant toward a lateral center of the implant.

5. The spinal implant of claim 1, wherein at least one of the first lateral wall and the second lateral wall comprises a tapered portion to facilitate insertion of the implant into the intervertebral space.

6. The spinal implant of claim 1, further comprising a plurality of prongs extending into the at least one internal chamber for retaining a graft or other fill materials located therein.

7. The spinal implant of claim 6, wherein the plurality of prongs are configured to engage and retain at least one of a sponge, a porous foam and cured grafting materials located within the at least one internal chamber of the implant.

8. The spinal implant of claim 1, wherein the implant is configured for placement within a lumbar or thoracic portion of a subject'"'"'s spine.

9. The spinal implant of claim 1, wherein the implant is configured for lateral insertion into the intervertebral space.

10. The spinal implant of claim 1, wherein the implant comprises polyether etherketone (PEEK).

11. The spinal implant of claim 1, wherein the at least one internal chamber does not comprise any interior walls or baffles.

12. The spinal implant of claim 1, wherein the at least one internal chamber comprises at least two internal sub-chambers divided by at least one interior wall.

13. The spinal implant of claim 1, wherein the implant comprises at least one radio-opaque marker.

14. The spinal implant of claim 1, wherein the at least one access port is generally circular.

15. The spinal implant of claim 1, wherein the at least one access port comprises a minimum diameter of approximately 6 mm.

16. The spinal implant of claim 1, wherein the at least one access port is adapted to receive a fill conduit therethrough, said fill conduit being configured to selectively deliver a grafting material into the at least one internal chamber of the implant.

17. The spinal implant of claim 1, wherein a minimum ratio of a diameter of the at least one access port to a height of the first or second lateral wall through which the at least one access port is located is approximately 0.5.

18. An implant configured for placement within an intervertebral space of a patient'"'"'s spine, comprising:

an anterior wall and a posterior wall, said posterior wall being generally opposite of said anterior wall;

lateral walls extending between the anterior wall and the posterior wall, said lateral walls, the anterior wall and the posterior wall defining an internal chamber of the implant;

wherein the internal chamber extends at least partially from the top surface to the bottom surface of the implant;

a plurality of openings within the anterior wall, said openings being configured to place the internal chamber in fluid communication with an exterior of the implant;

at least one port located in the lateral walls, wherein the implant is configured to releasably secure to an insertion tool using said at least one port;

wherein each of the first and second lateral walls is configured to generally align with peripheral bearing areas of the first and second vertebral bodies and to support adjacent cortical rims of the first and second vertebral bodies, such that the implant spans across an entire width of the first and second vertebral bodies of a mature adult human being;

wherein the at least one port is configured to provide a passage though which a graft fill tube selectively passes to reach the internal chamber;

wherein the posterior wall does not comprise any openings;

wherein excess graft material delivered into the internal chamber through the at least one port is configured to exit the implant through the openings of the anterior wall;

wherein a lateral axis that extends laterally between the anterior wall and the posterior wall is generally linear; and

wherein a length of each of the lateral walls is a minimum of 12% of an overall length of the implant.

19. The implant of claim 18, wherein a ratio of a diameter of the at least one port to a height of the lateral walls is between approximately 0.4 and 0.8.

20. The implant of claim 18, wherein a minimum ratio of a diameter of the at least one port to a height of the lateral walls is approximately 0.5.