PROSTHESIS FOR SIMULATING NATURAL KINEMATICS

• US 20110106265A1
• Filed: 10/31/2008
• Published: 05/05/2011
• Est. Priority Date: 11/02/2007
• Status: Active Grant

• Current Assignee: Biomet Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Lloyd, Russell, Khan, Mohammed Imran, Dodo, Christopher, Murray, David Wycliffe, O'connor, John, Goodfellow, John W., Wolfson, David
• Granted Patent: US 8,470,048 B2
• Time in Patent Office: Days
• US Class Current: 623/18.11
• CPC Class Codes: A61F 2/08 Muscles; Tendons; Ligaments sutures A61B17/04
• CPC Class Codes: A61F 2/0811 Fixation devices for tendons or ligaments
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/3836 Special connection between upper and lower leg, e.g. constrained
• CPC Class Codes: A61F 2/3868 with sliding tibial bearing
• CPC Class Codes: A61F 2002/0847 Mode of fixation of anchor to tendon or ligament
• CPC Class Codes: A61F 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: Y10T 29/49707 Bearing surface treatment

Abstract

A bearing component 2 for a joint replacement prosthesis comprises a first bearing element 4; a second bearing element 6, and a linking element 8, operatively connecting the first and second bearing elements 4, 6 and permitting relative motion there between. The flexible linking element 8 prevents dislocation of mobile bearings in a total knee replacement prosthesis. The invention also relates to a bridging element which retains the linking element 8 with some play, which acts as a ligament support 2051, and which causes a deflection of the line of action of a ligament 1018.

A joint replacement prosthesis is also disclosed comprising a biasing element 1140 or a tensioning element 1220 operatively coupled to the artificial ligament 1018. The biasing element 1140 or tensioning element 1220 may be housed in the stem of a tibial tray 1006.

Claims

1. A joint replacement prosthesis comprising:

a bearing component including,

a first bearing element,

a second bearing element, and

a linking element, operatively connecting the first and second bearing

elements and permitting relative motion there between.

2. The joint replacement prosthesis as claimed in claim 1, wherein the linking element is flexible.

3. The joint replacement prosthesis as claimed in claim 1, wherein the linking element is elastic or resilient.

4. The joint replacement prosthesis as claimed in claim 1, wherein the first and second bearing elements and the linking element are integrally formed.

5. The joint replacement prosthesis as claimed in claim 1, wherein the linking element comprises a polyethylene membrane.

6. The joint replacement prosthesis as claimed in claim 1, wherein the linking element comprises a fabric or polyester cord.

7. The joint replacement prosthesis as claimed in claim 6, wherein respective ends of the linking element are moulded into the first and second bearing elements.

8. The joint replacement prosthesis as claimed in claim 1, further comprising first and second bone engaging components that articulate via the bearing component.

9. The joint replacement prosthesis as claimed in claim 8, wherein the prosthesis is a knee replacement prosthesis, the first bone engaging component comprising a femoral component and the second bone engaging component comprising a tibial component.

10. The joint replacement prosthesis as claimed in claim 9, wherein the bearing component is supported on the tibial component such that relative motion between the tibial component and first and second bearing elements is enabled.

12. The joint replacement prosthesis as claimed in claim 10, wherein the tibial component comprises at least one tray, on which the bearing component is supported, and a retaining element that extends across the tray, between the first and second bearing elements, passing over the linking element.

13. The joint replacement prosthesis as claimed in claim 12, wherein the retaining element comprises a bridge, under which the linking element of the bearing component passes, such that the bridge limits the extent of relative motion possible between the linking element and the tibial tray.

14. The joint replacement prosthesis as claimed in claim 12, wherein the retaining element is removably connected to the tibial tray.

15. The joint replacement prosthesis as claimed in claim 12, further comprising an artificial ligament.

16. The joint replacement prosthesis as claimed in claim 15, wherein the artificial ligament extends between and is connected to the tibial and femoral components.

17. The joint replacement prosthesis as claimed in claim 16 wherein the retaining element is adapted to engage the artificial ligament over at least a portion of a range of motion of the ligament.

18. The joint replacement prosthesis as claimed in claim 17, wherein the retaining element is adapted to deflect the artificial ligament to change a line of action of the artificial ligament.

19. The joint replacement prosthesis as claimed in claim 18, wherein the retaining element is formed with a chamfer, recess or projection for engagement with the artificial ligament.

20. The joint replacement prosthesis as claimed in claim 10, wherein the tibial component comprises first and second bearing surfaces, operable to articulate with the first and second bearing elements of the bearing component, the first bearing surface being convex and the second bearing surface being non con-convex.

23. A method of making the bearing component as claimed in claim 1, comprising direct compression moulding ends of the linking element into the first and second bearing elements.

24. A method of making the bearing component as claimed in claim 1, comprising moulding the first and second bearing elements as a single piece and removing material from the area between the first and second bearing components to define the linking element.

11. (canceled)

21-22. -22. (canceled)

25-77. -77. (canceled)