Intervertebral disc prosthesis

• US 7,628,814 B2
• Filed: 09/01/2005
• Issued: 12/08/2009
• Est. Priority Date: 03/24/2003
• Status: Expired due to Fees

• Current Assignee: Synthes USA LLC (Johnson & Johnson)
• Original Assignee: Synthes USA LLC (Johnson & Johnson)
• Inventors: Trachsel, Jason, Wymann, Martin, Studer, Armin
• Primary Examiner(s): Barrett; Thomas C
• Assistant Examiner(s): Bates; David W
• Application Number:
  US11/219,590
• Publication Number:
  US 20060052872A1
• Time in Patent Office: 1,559 Days
• Field of Search: 606247-249, 623/17.13, 623/17.15, 623/17.16, 222/492
• US Class Current: 623/17.11
• 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 including an upper apposition plate appropriate to rest against the base plate of an upper vertebra, a lower apposition plate spaced apart from the upper apposition plate and suitable to rest against the base plate of a lower 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 having a longitudinal axis, the prosthesis comprising:

a first plate having a first plate longitudinal axis, the first plate configured to engage a first vertebrae;

a second plate having a second plate longitudinal axis, the second plate configured to engage a second vertebrae; and

first and second helical spring elements disposed at least partially between the first and second plates, the first and second helical spring elements being coaxially aligned in a series along the longitudinal axis of the prosthesis, each of the first and second helical spring elements including a lumen defining a longitudinal axis such that the longitudinal axis of the first and second helical spring elements, the first plate longitudinal axis and the second plate longitudinal axis are all parallel to the longitudinal axis of the prosthesis;

wherein the first helical spring element has a first stiffness, and the second helical spring element has a second stiffness; and

wherein the first stiffness is greater than the second stiffness.

2. The prosthesis of claim 1, wherein the first helical spring element is comprised of a different material than the second helical spring element.

3. The prosthesis of claim 1, wherein the first and second helical spring elements are substantially equally sized.

4. The prosthesis of claim 1, wherein the first and second helical spring elements have substantially different cross-sections.

5. The prosthesis of claim 1, wherein the first helical spring element is more tightly coiled than the second helical spring element.

6. The prosthesis of claim 1, wherein the first and second plates are rectangular.

7. The prosthesis of claim 1, wherein the first and second helical spring elements have mutually opposite turn pitches.

8. The prosthesis of claim 1, wherein the first and second helical spring elements each include a plurality of turns and the first and second plates each include an elevation extending from an inner surface thereof, the elevation being parallel to the longitudinal axis of the prosthesis, each elevation including a plurality of boreholes running transversely to the longitudinal axis of the prosthesis, each borehole receiving one of the turns of the first and second helical spring elements.