Multiple axis intervertebral prosthesis

• US 6,228,118 B1
• Filed: 08/04/1998
• Issued: 05/08/2001
• Est. Priority Date: 08/04/1997
• Status: Expired due to Fees

• Current Assignee: Gordon, Maya, Roberts And Thomas, Number 1, LLC
• Original Assignee: Gordon, Maya, Roberts And Thomas, Number 1, LLC
• Inventors: Gordon, Dennis P.
• Primary Examiner(s): Willse, David H.
• Assistant Examiner(s): Stewart, Alvin
• Application Number:
  US09/128,756
• Time in Patent Office: 1,008 Days
• Field of Search: 623/17, 623/17.11, 623/17.12, 623/17.13, 623/17.14, 623/17.15, 623/17.16, 623/17.17, 623/17.18, 623/19.12, 623/20.22, 623/21.13, 623/21.16
• US Class Current: 623/17.14
• CPC Class Codes: A61B 17/68 Internal fixation devices , including fasteners and spinal fixators, even if a part thereof projects from the skin bone staples A61B17/0642
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/4425 made of articulated components
• CPC Class Codes: A61F 2002/3013 figure-"8"- or hourglass-shaped
• CPC Class Codes: A61F 2002/302 toroidal, e.g. rings
• CPC Class Codes: A61F 2002/30225 Flat cylinders, i.e. discs
• CPC Class Codes: A61F 2002/3023 wedge-shaped cylinders
• CPC Class Codes: A61F 2002/30578 having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30662 with rotation-limiting means
• CPC Class Codes: A61F 2002/30777 Oblong apertures
• CPC Class Codes: A61F 2002/30787 inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/3079 Stepped or enlarged apertures, e.g. having discrete diameter changes
• CPC Class Codes: A61F 2002/30934 Special articulating surfaces
• CPC Class Codes: A61F 2002/443 having two transversal endplates and at least one intermediate component
• CPC Class Codes: A61F 2002/4631 the prosthesis being specially adapted for being cemented
• CPC Class Codes: A61F 2230/001 Figure-8-shaped, e.g. hourglass-shaped
• CPC Class Codes: A61F 2230/0065 : toroidal, e.g. ring-shaped, doughnut-shaped
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2310/00011 : Metals or alloys
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00179 : Ceramics or ceramic-like structures
• CPC Class Codes: A61F 2310/00592 : Coating or prosthesis-covering structure made of ceramics or of ceramic-like compounds

Abstract

The present invention relates to an intervertebral prosthetic disk. The prosthesis comprises a male component with a support plate, an attachment element allowing fixation to a vertebra, and an articulating projection, and a female component with a support plate, an attachment element allowing fixation to a vertebra, and a circular pocket with angled walls suitable for receiving the articulating projection. The male component is placed inside the female component, and the two components are attached to the adjacent vertebrae and act as a replacement for a disk. The prosthesis allows for a natural range of motion for the patient.

Claims

1. An intervertebral prosthetic disk comprising:

a) a male component comprising a first support plate, a first attachment element allowing fixation to a vertebra, and an articulating projection including a first radius of curvature; and

b) a female component comprising a second support plate having an upper surface, a second attachment element allowing fixation to a vertebra, and a circular pocket with angled walls having a second radius of curvature larger than the first radius of curvature and suitable for receiving the articulating projection;

wherein the pocket has a circular cross section in a plane substantially parallel to the upper surface of the second support plate.

2. The prosthetic disk of claim 1, wherein the first and second attachment elements each comprise at least one vertical flange extending from the support plate and contain at least one opening through which a mechanical attachment element can pass.

3. The prosthetic disk of claim 2, wherein the mechanical attachment element comes from the group consisting of screws, pegs and rods.

4. The prosthetic disk of claim 3 wherein the number of openings and mechanical attachment elements is at least two on both the male and female components.

5. The prosthetic disk of claim 1, wherein the first and second attachment elements are a porous coating for permanent bony fixation on a bone-facing surface of the support plates.

6. The prosthetic disk of claim 1, wherein the first and second attachment elements each comprise at least one flange, at least one mechanical attachment element, and a porous coating on a bone-facing surface of the support plates.

7. The prosthetic disk in claim 1, wherein the first support plate is wedge-shaped to facilitate building lordosis.

8. The prosthetic disk of claim 1, wherein at least one of the components is made of a material selected from the group consisting of ceramics and metal alloys.

9. The prosthetic disk of claim 1, wherein both of the components are made of a metal alloy.

10. The prosthetic disk of claim 9, where the metal alloy is chromium cobalt.

11. The prosthetic disk of claim 1, wherein the articulating projection is doughnut shaped to facilitate range of motion.

12. The prosthetic disk of claim 1 wherein the angled walls of the circular pocket allow the male component to self-center within the female component.

13. The prosthetic disk of claim 7 wherein the wedge shaped plate comprises a recessed, angled hole through which an attachment element can pass.

14. The prosthetic disk of claim 13 wherein the attachment element is a screw.

15. The prosthetic disk of claim 1 wherein the second support plate comprises a recessed, angled hole through which an attachment element can pass.

16. The prosthetic disk of claim 15 wherein the attachment element is a screw.

17. The prosthetic disk of claim 2 wherein the flange includes at least one opening selected from the group consisting of circular, oval, and figure-eight patterns.

18. The disk recited in claim 1 wherein the articulating projection, when inside the circular pocket, provides multiple centers of rotation for flexion, extension, and lateral flexion and rotation.

19. The disk recited in claim 1 wherein the mechanism allows for at least approximately 15 degrees of flexion, 5 degrees of extension, 1 degree of rotation and 5 degrees of lateral bending.

20. An intervertebral prosthetic disk comprising:

a) a male component comprising an articulating projection with a neck having a first radius of curvature and a protrusion having a second radius of curvature;

b) a female component comprising a pocket with angled walls having a third radius of curvature larger than the second radius of curvature which can receive the articulating projection of the male component;

wherein the articulating projection contacts the pocket along at least a portion of a path extending around the walls of the pocket.

21. An intervertebral prosthetic disk recited in claim 20 wherein a coating or insert is provided on the inside surface of the pocket.

22. The intervertebral prosthetic disk recited in claim 21 wherein the coating or insert is either plastic or ceramic.

23. An intevertebral prosthetic disk comprising:

a) a male component comprising a first means for supporting, a first means for attaching allowing fixation to a vertebra, and an articulating projection defined by a protrusion having a first radius of curvature;

b) a female component comprising a second means for supporting, a second means for attaching allowing fixation to a vertebra, and a circular pocket with angled walls defining a second radius of curvature larger than the first radius of curvature suitable for receiving the protrusion of the articulating projection;

wherein the articulating projection contacts the pocket along at least a portion of a path extending around the walls of the pocket.

24. An intervertebral prosthetic disk comprising:

a) a male component comprising a first support plate having a lower surface, a first attachment element allowing fixation to a vertebra, and an articulating projection including a first radius of curvature; and

b) a female component comprising a second support plate, a second attachment element allowing fixation to a vertebra, and a circular pocket with angled walls having a second radius of curvature larger than the first radius of curvature and suitable for receiving the articulating projection;

wherein the articulating projection has a circular cross section in a plane substantially parallel to the lower surface of the first support plate.

25. An intervertebral prosthetic disk comprising:

a) a male component comprising a first support plate, a first attachment element allowing fixation to a vertebra, and an articulating projection including a first radius of curvature; and

b) a female component comprising a second support plate, a second attachment element allowing fixation to a vertebra, and a circular pocket with angled walls having a second radius of curvature larger than the first radius of curvature and suitable for receiving the articulating projection;

wherein the articulating projection contacts the pocket along at least a portion of a path extending around the walls of the pocket.