Intervertebral disc prosthesis

• US 20060052872A1
• Filed: 09/01/2005
• Published: 03/09/2006
• Est. Priority Date: 03/24/2003
• Status: Active Grant

• Current Assignee: Synthes USA LLC (Johnson & Johnson)
• Original Assignee: Synthes USA LLC (Johnson & Johnson)
• Inventors: Wymann, Martin, Studer, Armin, Trachsel, Jason
• Granted Patent: US 7,628,814 B2
• Time in Patent Office: Days
• US Class Current: 623/17.130
• CPC Class Codes: A61F 2/4425 made of articulated components
• CPC Class Codes: A61F 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/30113 circular
• CPC Class Codes: A61F 2002/30125 elliptical or oval
• CPC Class Codes: A61F 2002/302 toroidal, e.g. rings
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30518 with possibility of relative movement between the prosthetic parts
• CPC Class Codes: A61F 2002/30565 having spring elements
• CPC Class Codes: A61F 2002/30568 Multiple spring systems including two or more helical springs
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/443 having two transversal endplates and at least one intermediate component
• CPC Class Codes: A61F 2002/444 for replacing the nucleus pulposus
• 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 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0041 using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2230/0008 elliptical or oval
• CPC Class Codes: A61F 2230/0065 toroidal, e.g. ring-shaped, doughnut-shaped
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite

Abstract

Intervertebral disc prosthesis comprising an upper apposition plate appropriate to rest against the base plate of a vertebra, an apposition plate spaced apart from the apposition plate and suitable to rest against the upper plate of a vertebra, a plurality of elastic devices mounted between the two apposition plates and in their peripheral zones in a manner that the two apposition plates shall be displaceable in mutually resilient manner, and a central axis which runs essentially perpendicularly to the two apposition plates, the elastic devices being designed/configured in a manner that the intervertebral disc prosthesis as a whole exhibits asymmetrical stiffness.

Claims

1. An intervertebral disc prosthesis comprising:

a first plate configured to engage a first vertebrae;

a second plate configured to engage a second vertebrae; and

first and second elastic elements disposed at least partially between the first and second plates;

wherein the first elastic element has a greater stiffness than the second elastic element, such that the prosthesis is more stiff in a first direction than in a second direction.

2. The prosthesis of claim 1, further comprising an outer perimeter, and wherein the first and second elastic elements are disposed at different locations proximate the outer perimeter.

3. The prosthesis of claim 1, wherein the first elastic element is substantially ring-shaped.

4. The prosthesis of claim 1, wherein the first elastic element is comprised of a different material than the second elastic element.

5. The prosthesis of claim 1, further comprising a third elastic element.

6. The prosthesis of claim 1, wherein at least the first plate is substantially round.

7. The prosthesis of claim 1, wherein at least the first plate has a central opening.

8. The prosthesis of claim 1, wherein the first and second elastic elements are substantially equally sized.

9. The prosthesis of claim 1, wherein the first and second elastic elements have substantially different cross-sections.

10. An intervertebral disc prosthesis comprising:

a first plate configured to engage a first vertebrae;

a second plate configured to engage a second vertebrae;

an outer perimeter;

a central axis substantially perpendicular to the first and second plates; and

a first elastic element disposed at least partially between the first and second plates, and at least partially disposed proximate the outer perimeter;

wherein the prosthesis is asymmetrically stiff with respect to the central axis.

11. The prosthesis of claim 10, further comprising a second elastic element disposed at least partially between the first and second plates, and at least partially disposed proximate the outer perimeter.

12. The prosthesis of claim 10, further comprising a plurality of elastic elements, and wherein the elastic elements are substantially evenly spaced along the outer perimeter.

13. The prosthesis of claim 10, wherein the prosthesis is configured to be more stiff in a rearward direction than in a forward direction.

14. The prosthesis of claim 10, wherein at least a portion of the first elastic element extends beyond the outer perimeter.

15. An intervertebral disc prosthesis comprising:

a first plate configured to engage a first vertebrae;

a second plate configured to engage a second vertebrae; and

a coiled elastic element disposed at least partially between the first and second plates;

wherein the coiled elastic element has a first portion having a first stiffness, and a second portion having a second stiffness; and

wherein the first stiffness is greater than the second stiffness, such that the prosthesis is more stiff in a first direction than in a second direction.

16. The prosthesis of claim 15, wherein the first portion of the coiled elastic element is more tightly coiled than the second portion.

17. The prosthesis of claim 15, wherein the first direction is substantially perpendicular to the second direction.

18. The prosthesis of claim 15, further comprising an outer perimeter, and wherein the coiled elastic element extends substantially around the outer perimeter.

19. The prosthesis of claim 15, further comprising another elastic element.

20. The prosthesis of claim 15, wherein at least the first plate is substantially oval.