INTERVERTEBRAL IMPLANT AND METHODS OF IMPLANTATION AND MANUFACTURE

• US 20090292362A1
• Filed: 05/20/2008
• Published: 11/26/2009
• Est. Priority Date: 05/20/2008
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Inventors: FRANCIS, Tom J., ECKHARDT, Jason J., ALLARD, Randall N., ALBANS, William J., CARLS, Thomas A.
• Granted Patent: US 8,518,113 B2
• Time in Patent Office: Days
• US Class Current: 623/17.16
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• 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 2/4425 made of articulated components
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/3008 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2002/30242 spherical
• CPC Class Codes: A61F 2002/30252 quadric-shaped
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30639 having rolling elements between both articulating surfaces
• CPC Class Codes: A61F 2002/30673 Lubricating means, e.g. synovial pocket
• CPC Class Codes: A61F 2002/30838 Microstructures
• CPC Class Codes: A61F 2002/30957 using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2230/0071 spherical
• CPC Class Codes: A61F 2230/0073 Quadric-shaped
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers

Abstract

In one aspect, an intervertebral prosthetic device for implantation within a disc space between adjacent first and second vertebral endplates includes a body including a main body with an outer surface bearing portion configured to interface with and articulate relative to one of the first and second vertebral endplates. It also comprises an orientation protrusion shaped in a manner to at least partially inhibit rotation of the body in the disc space. The body is sized in at least one direction to fit inside a boundary defined by a travel path of the first vertebra relative to the second vertebra, the travel path forming an arc about a center of rotation of the first vertebra, the travel path being spaced from the center of rotation a distance substantially equivalent to the distance from the center of rotation to the second vertebral endplate.

Claims

1. An intervertebral prosthetic device for implantation within a disc space between adjacent first and second vertebral endplates, comprising:

a body including a main body with an outer surface bearing portion configured to interface with at least one of and articulate relative to at least one of the first and second vertebral endplates, and including an orientation protrusion shaped in a manner to at least partially inhibit rotation of the body in the disc space;

the body being sized in at least one direction to fit inside a boundary defined by a travel path of the first vertebra relative to the second vertebra, the travel path forming an arc about a center of rotation of the first vertebra, the travel path being spaced from the center of rotation a distance substantially equivalent to the distance from the center of rotation to the second vertebral endplate or vice versa.

2. The prosthetic device of claim 1, wherein the body is non-symmetrical such that the body is sized to fit inside the boundary in one direction and sized such that the body does not fit within the boundary in a transverse direction.

3. The prosthetic device of claim 1, wherein the bearing surface has a first radius of curvature in the at least one direction and a second radius of curvature in a direction transverse to the at least one direction, wherein the first radius of curvature and the second radius of curvature are different.

4. The prosthetic device of claim 1, wherein the device is formed of a polymeric material.

5. The prosthetic device of claim 1, wherein the device is formed of at least one of PEEK and polyurethane.

6. The prosthetic device of claim 1, further including a coating about the main body configured to provide lubricity between the outer surface and at least one of the first and second vertebral endplates.

7. The prosthetic device of claim 1, wherein the device is sized and shaped to provide impingement free articulation through a flexion/extension range equal to or greater than 15 degrees.

8. The prosthetic device of claim 1, wherein the bearing portion forms a hemispherical surface.

9. The prosthetic device of claim 1, wherein the bearing surface is cylindrical.

10. The prosthetic device of claim 1, further including a prosthetic endplate configured to interface directly with the first or second vertebral endplate, the prosthetic endplate being configured for disposal between the first or second vertebral endplate and the main body.

11. An intervertebral prosthesis implantable within a disc space, disposed between upper and lower vertebral endplates, comprising:

a main body formed of medical-grade polymeric material, the main body having an outer surface comprising an upper bearing portion and a lower bearing portion, at least one of the upper and lower bearing portions being configured to articulate relative to one of the upper and lower vertebral endplates, the at least one of the upper and lower bearing portions including fluid-receiving pores and having a hardness that permits deformation of the main body to expel the fluid from the pores under a load applied by the respective upper or lower vertebral endplate.

12. The intervertebral prosthesis of claim 11, wherein the polymeric material has a hardness within the range of 80-90 Durometer Shore D.

13. The intervertebral prosthesis of claim 11, including a film coating on the main body, the film coating being one of a lubricating agent, a wetting agent, and a bone morphogenetic protein.

14. The intervertebral prosthesis of claim 11, further comprising a prosthesis endplate configured to interface with one of the upper bearing portion and the lower portion and configured to interface with one of the upper and lower vertebral endplates.

15. The intervertebral prosthesis of claim 11, wherein the main body has one of a generally spherical shape, a generally ellipsoidal shape, and a generally paraboloidal shape.

16. The intervertebral prosthesis of claim 11, wherein the main body has a first cross-sectional generally rectangular shape and a second cross-sectional generally oval shape.

17. The intervertebral prosthesis of claim 11, wherein the surface has a relatively rough area and a relatively smooth area.

18. The intervertebral prosthesis of claim 11, further comprising a marker of a radiopaque material.

19. The intervertebral prosthesis of claim 11, further comprising:

a first marker positioned in a first segment of the prosthesis, and a second marker positioned in a second segment of the prosthesis; and

the first marker being remotely distinguishable from the second marker.

20. The intervertebral prosthesis of claim 11, wherein the medical-grade olymeric material is one of a polyetheretherketone (PEEK) and a polyurethane (PU).