INTERVERTEBRAL IMPLANT

• US 20100094421A1
• Filed: 10/06/2009
• Published: 04/15/2010
• Est. Priority Date: 02/19/2002
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Christopher Marden John Cain, Claude Mathieu
• Inventors: Mathieu, Claude, Cain, Christopher Marden John
• Granted Patent: US 7,875,076 B2
• Time in Patent Office: Days
• US Class Current: 623/17.15
• 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. An intervertebral implant for insertion between an upper vertebra having an upper endplate and a lower vertebra having a lower endplate, the implant comprising:

a body having a first lateral side surface, a second lateral side surface, a posterior face, an anterior face, an upper surface and a lower surface, the upper and lower surfaces being sized and configured to contact the upper and lower endplates, respectively, of the upper and lower vertebrae, the upper surface defining an upper plane and the lower surface defining a lower plane;

a plate operatively coupled to the body, the plate having a plate top surface located generally on the upper plane and a plate lower surface located generally on the lower plane when the plate is coupled to the body so that the body has a first height extending between the upper surface and the lower surface and the plate has a second height extending between the plate top surface and the plate lower surface, the second height being generally equal to the first height, first and second boreholes passing through the plate; and

first and second bone screws each having a head and a shank, the first bone screw extending through the first borehole into the upper endplate and the second bone screw extending through the second borehole into the lower endplate to anchor the intervertebral implant to the upper and lower vertebrae and the heads of the first and second bone screws positioned between the upper and lower planes.

2. The implant of claim 1, wherein the implant includes a plurality of teeth.

3. The implant of claim 1, wherein the plate contacts the anterior face of the body.

4. The implant of claim 3, wherein the anterior face of the body includes a recess for receiving the plate.

5. The implant of claim 1, wherein the plate is entirely contained between the endplates of the upper and lower vertebrae when the implant is inserted between the upper and lower vertebrae.

6. The implant of claim 1, wherein the body and the plate are pre-assembled so that the body and the plate are inserted between the upper and lower vertebrae as a single unit.

7. The implant of claim 1, wherein the implant includes a vertical center plane, the first and second fasteners being laterally divergent from the vertical center plane.

8. The implant of claim 1, wherein the body comprises a horizontal center plane and the plate is disposed substantially perpendicular to the horizontal center plane.

9. The implant of claim 1, wherein the body comprises a horizontal center plane and the plate is displaceable in a direction substantially perpendicular to the horizontal center plane.

10. The implant of claim 1, wherein the body is formed from a first biocompatible material and the plate is formed from a second biocompatible material, the second biocompatible material being different than the first biocompatible material.

11. The implant of claim 10, wherein the plate is made from a biocompatible metal and the body is made from a biocompatible plastic.

12. The implant of claim 1, wherein the body comprises a horizontal center plane and the first and second fastener holes have an axis angled from about twenty-five degrees (25°

) to about seventy degrees (70°

) with respect to the horizontal center plane.

13. The implant of claim 12, wherein the axis is angled from about thirty-five degrees (35°

) to about fifty degrees (50°

) with respect to the horizontal center plane.

14. The implant of claim 1, wherein the plate is slidably displaceable with respect to the body.

15. The implant of claim 1, wherein the first and second fasteners are bone screws and wherein the first and second fastener holes formed in the plate are internally threaded and the heads of the bone screws are externally threaded for engaging the internally threaded holes.

16. The implant of claim 1, wherein the plate further comprises a horizontal center midplane, the head of the first fastener being located between the top surface of the plate and the horizontal center midplane and the head of the second fastener being located between the bottom surface of the plate and the horizontal center midplane.