Intervertebral implant

• US 20050177236A1
• Filed: 08/19/2004
• Published: 08/11/2005
• Est. Priority Date: 02/19/2002
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Synthes GmbH (Johnson & Johnson)
• Inventors: Mathieu, Claude, Cain, Christopher Marden John
• Granted Patent: US 7,232,464 B2
• Time in Patent Office: Days
• US Class Current: 623/17.110
• CPC Class Codes: A61B 17/8052 immobilised relative to screws by interlocking form of the heads and plate holes, e.g. conical or threaded
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• 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 2002/30004 the prosthesis being made from materials having different values of a given property at different locations within the same prosthesis
• 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 2002/3079 Stepped or enlarged apertures, e.g. having discrete diameter changes
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2250/0014 having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis
• CPC Class Codes: A61F 2310/00011 Metals or alloys

Abstract

The intervertebral implant is in the form of a three-dimensional structure (10) comprising (a) a top side (1) and an underside (2) which are designed to rest against the end plates of two adjacent vertebras, (b) a left side face (3) and a right side face (4), (c) a front face (5) and a rear face (6), (d) a horizontal center plane situated between the top side (1) and the underside (2), (e) a vertical center plane (8) situated between the left side face (3) and the right side face (8) and (f) a plurality of boreholes (9) passing through the implant structure (10) that are designed to receive longitudinal affixation elements (20), the axes (19) of said elements intersecting the horizontal center plane (7). At least one of the boreholes (9) is designed in a manner that the affixation element (10) received in it can be rigidly connected to the intervertebral implant. Said connection is implemented using a thread or by matching conical surfaces.

Claims

1. A intervertebral implant comprising:

an upper surface at least partially configured to lie adjacent to the endplate of a first vertebrae;

a lower surface at least partially configured to lie adjacent to the endplate of a second vertebrae;

a plane located approximately halfway between the upper surface and the lower surface, the plane being substantially parallel to at least a portion of the upper and lower surfaces;

a plurality of side surfaces, including a front surface and a rear surface;

a first borehole having a first end located at a side surface and substantially below the plane, and a second end located at the upper surface; and

a second borehole having a first end located at a side surface and substantially above the plane, and a second end located at the lower surface.

2. The implant of claim 1, wherein the first and second boreholes are configured to receive at least a portion of a bone fastener.

3. The implant of claim 2, wherein at least one bone fastener is configured to engage the endplate of a vertebrae.

4. The implant of claim 3, wherein at least one bone fastener is a bone screw.

5. The implant of claim 3, wherein at least one bone fastener is an attachment pin.

6. The implant of claim 3, wherein at least one bone fastener is a spiral spring.

7. The implant of claim 3, wherein at least one bone fastener is a winged spiral blade.

8. The implant of claim 1, wherein at least one of the first and second boreholes is a least partially threaded.

9. The implant of claim 1, wherein at least one of the first and second boreholes is tapered from the first end to the second end.

10. The implant of claim 9, wherein a tapered borehole is at least partially conical.

11. The implant of claim 10, wherein the tapered borehole has a conicity of between about 1:

3.75 to about 1;

20.

12. The implant of claim 10, wherein the tapered borehole has a conicity of between about 1:

5 to about 1;

15.

13. The implant of claim 1, wherein the front surface comprises a front plate, and wherein at least a portion of the first ends of the first and second boreholes are located in the front plate.

14. The implant of claim 13, wherein the front plate is comprised of a different material than that of the remainder of the implant.

15. The implant of claim 1, wherein the upper and lower surfaces are substantially convex.

16. The implant of claim 1, wherein at least a portion of the side surfaces are substantially convex.

17. The implant of claim 1, wherein the first borehole has a first axis, and the second borehole has a second axis, and wherein the first and second axes are askew.

18. The implant of claim 1, wherein the first borehole has a first axis, and the second borehole has a second axis, and wherein the first and second axes intersect.

19. The implant of claim 1, wherein the first borehole has a first axis forming a first angle with the upper surface, and the second borehole has a second axis forming a second angle with the lower surface, and wherein the first and second angles are acute.

20. The implant of claim 1, wherein the first borehole has a first axis forming a first angle with the upper surface, and the second borehole has a second axis forming a second angle with the lower surface, and wherein the first and second angles are obtuse.

21. The implant of claim 1, wherein the first borehole has a first axis forming a first angle with the upper surface, and the second borehole has a second axis forming a second angle with the lower surface, and wherein the first and second angles are substantially equal.

22. The implant of claim 1, wherein at least a portion of the implant is comprised of plastic.

23. The implant of claim 1, wherein at least a portion of the implant is comprised of metal.

24. The implant of claim 1, wherein at least a portion of at least one of the upper surface and lower surface includes teeth.

25. The implant of claim 1, wherein at least a portion of the implant is hollow, and wherein at least a portion of at least one of the upper surface and lower surface have perforations.