Spinal implant

• US 6,746,484 B1
• Filed: 09/29/2000
• Issued: 06/08/2004
• Est. Priority Date: 08/26/1997
• Status: Expired due to Term

• Current Assignee: Society de Fabrication de Materiel de Orthopedique SA
• Original Assignee: Society de Fabrication de Materiel de Orthopedique SA
• Inventors: Chopin, Daniel, Liu, Mingyan, Bouquet, Philippe, Meisel, Hans-Jorg
• Primary Examiner(s): Prebilic, Paul B.
• Application Number:
  US09/486,301
• Time in Patent Office: 1,348 Days
• Field of Search: 623/17.11, 623/17.16, 606/178, 606/184
• US Class Current: 623/17.16
• CPC Class Codes: A61B 17/025 Joint distractors
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• 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 2/4603 for insertion or extraction of endoprosthetic joints or of accessories thereof
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• 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 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30158 trapezoidal
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/30266 wedge-shaped parallelepipeds
• CPC Class Codes: A61F 2002/3028 polyhedral different from parallelepipedal and pyramidal
• CPC Class Codes: A61F 2002/30576 with extending fixation tabs
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30774 internally-threaded
• CPC Class Codes: A61F 2002/30777 : Oblong apertures
• CPC Class Codes: A61F 2002/30785 : parallel
• CPC Class Codes: A61F 2002/30789 : perpendicular with respect to each other
• CPC Class Codes: A61F 2002/30845 : with cutting edges
• CPC Class Codes: A61F 2002/448 : comprising multiple adjacent spinal implants within the same intervertebral space or within the same vertebra, e.g. comprising two adjacent spinal implants
• CPC Class Codes: A61F 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2210/0004 : bioabsorbable
• CPC Class Codes: A61F 2230/0026 : trapezoidal
• CPC Class Codes: A61F 2230/0063 : Three-dimensional shapes
• CPC Class Codes: A61F 2230/0082 : parallelepipedal
• CPC Class Codes: A61F 2310/00017 : Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00179 : Ceramics or ceramic-like structures

Abstract

A spinal cage implant (1) is adapted to be inserted in a damaged intervertebral disc for restoring the discal height and permitting an arthoesis. Implant (1) comprises a central part (3c) with walls (4) and terminal parts (5, 6) for bearing against the cortical bone (14) of the vertebral end plates (15, 16). Central part (3c) is adapted to penetrate the vertebral end plates (15, 16) and transversely projects from the terminal bearing parts (5, 6). Implant (1) bears against the vertebral end plates (15, 16) with terminal parts (5, 6) and contains bone graft material between walls (4) which penetrate the openings (19, 21) in the end plates (15, 16) and permit bone fusion between the two vertebrae (V1, V2). Implant (1) permits restoring the physiological lordosis and the intervertebral height

Claims

1. An implant for insertion between a first vertebra and a second vertebra, the first vertebra having a first cortical bone plate and the second vertebra having a second cortical bone plate, characterized in that the implant comprises:

a first terminal part defining a first bearing surface to bear against the first cortical bone plate, a second bearing surface opposite said first surface to bear against the second cortical bone plate;

a second terminal part opposite said first terminal part, said second terminal part defining a third bearing surface to bear against the first cortical bone plate and a fourth bearing surface opposite said third surface to bear against the second cortical bone plate;

an elongated central part including a pair of longitudinal walls having a generally trapezoid configuration defining a cavity therebetween each of said walls projecting transversely from the first and second terminal parts and including a tapering edge adapted to penetrate the first and second cortical bone plates, and

a projection extending transverse to said walls and positioned between said cavity and said first terminal part, said projection configured to correspondingly penetrate the first or second cortical bone plate when said first and third surfaces bear against the first cortical bone plate and said secondhand fourth surfaces bear against the second cortical bone plate.

2. The implant of claim 1 comprising a second projection opposite said projection, said second projection extending transverse to said walls and positioned between said cavity and said second terminal part, said projection configured to correspondingly penetrate the first or second cortical bone plate when said first and third surfaces bear against the first cortical bone plate and said second and fourth surfaces bear against the second cortical bone plate.

3. The implant of claim 1 wherein said first terminal part includes a first flange defining said first surface and a second flange defining said second surface;

and said second terminal part includes a third flange defining said third surface and a fourth flange defining said fourth surface.

4. The implant of claim 1 wherein said first, second, third, and fourth surfaces are generally flat.

5. The implant of claim 2 wherein the first projection, the second projection and the tapering edges of the longitudinal walls define an opening into the cavity.

14. The implant of claim 1 wherein the tapering edge of each of the longitudinal walls extends in a longitudinal direction.

15. The implant of claim 1, wherein said walls each have a generally trapezoidal contour.

16. The implant of claim 1, wherein said cavity holds bone graft material.

17. The implant of claim 1, wherein at least a portion of the implant is composed of a porous material.

18. The implant of claim 1, wherein said first and second surfaces are separated by a first distance and said third and fourth surfaces are separated by a second distance greater than said first distance to accommodate a spinal curvature.

6. An implant for insertion between opposing endplates of adjacent vertebrae, said implant comprising:

an elongate body defining a longitudinal axis and having a cavity therein;

said body comprising;

a first end including a first planar surface and an opposite second planar surface, said first and second planer surfaces configured to engage with the opposing endplates of the adjacent vertebrae;

a second end including a third planar surface and an opposite fourth planar surface, said third and fourth planer surfaces configured to engage with the opposing endplates of the adjacent vertebrae;

first and second longitudinal walls extending from the first end to the second end, each of said first and second walls having a first tapering edge and an opposite second tapering edge wherein the first and second edges are configured to penetrate the opposing endplates of the adjacent vertebrae;

a first projection extending from the first planar surface in a direction generally transverse to the longitudinal axis, said first projection positioned adjacent the cavity, disposed between the first and second longitudinal walls, and configured to penetrate one of the adjacent vertebrae, and

a third projection extending from the third planar surface in a direction generally transverse to the longitudinal axis, said third projection positioned adjacent the cavity, disposed between the first and second longitudinal walls and configured to penetrate one of the adjacent vertebrae.

7. The implant of claim 6 comprising:

a second projection extending from the second planar surface in a direction generally transverse to the longitudinal axis and opposite said first projection; and

,

a fourth projection extending from the fourth planar surface in a direction generally transverse to the longitudinal axis and opposite said third projection.

8. The implant of claim 6 wherein the first tapering edges of the first and second longitudinal walls, the first projection, and the third projection define an opening into the cavity.

9. The implant of claim 6 wherein at least a portion of the implant is composed of a resorbable material.

10. The implant of claim 6 comprising a flange extending from the first end.

11. The implant of claim 10 comprising a flange extending from the second end.

12. The implant of claim 6 comprising a first opening and an opposite, second opening into the cavity to define a passageway through the implant in a direction traverse to the longitudinal axis.

13. The implant of claim 12 comprising a bone graft material in the cavity to contact spongy bone of the opposing vertebrae.