Knee joint prosthesis system and method for implantation

• US 8,163,028 B2
• Filed: 08/05/2009
• Issued: 04/24/2012
• Est. Priority Date: 01/10/2007
• Status: Active Grant

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Metzger, Robert, Watson, Audra, Belcher, Nathan E.
• Primary Examiner(s): Isabella, David
• Assistant Examiner(s): Sharma, Yashita
• Application Number:
  US12/536,056
• Publication Number:
  US 20090299482A1
• Time in Patent Office: 993 Days
• Field of Search: 623/20.14, 623/20.15, 623/20.21, 623/20.32, 623/20.34, 623/20.35, 623/20.36
• US Class Current: 623/20.36
• CPC Class Codes: A61F 2/30721 Accessories
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/385 also provided with condylar bearing surfaces
• CPC Class Codes: A61F 2/3868 with sliding tibial bearing
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30339 Double cones, i.e. connecting element having two conical connections, one at each of its opposite ends
• CPC Class Codes: A61F 2002/30364 Rotation about the common longitudinal axis
• CPC Class Codes: A61F 2002/30369 Limited lateral translation of the protrusion within a larger recess
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/3069 Revision endoprostheses
• CPC Class Codes: A61F 2002/30736 Augments or augmentation pieces, e.g. wedges or blocks for bridging a bone defect
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit

Abstract

A prosthesis for replacing a knee joint between a femur and a tibia can include a femoral component having a first condylar portion, a second condylar portion, a first sidewall and a second sidewall that collectively comprise a first hinge portion. A tibial component can have a first engagement portion formed thereon. A bearing can have an articulating inferior surface adapted to articulate along the bearing. The bearing can have an opening. A yoke can have an inferior portion and superior portion, the superior portion having an axle that comprises a second hinge portion. The inferior portion can have a second engagement portion and be configured to at least partially pass through the opening. The femoral component is operable to rotate relative to the tibial component about a superior/inferior axis a first rotational distance until the first and second engagement portions engage each other and inhibit further rotation.

Claims

1. A prosthesis for replacing a knee joint between a femur and a tibia, the prosthesis comprising:

a femoral component including a first condylar portion, a second condylar portion, a first sidewall extending superiorly from the first condylar portion, a second sidewall extending superiorly from the second condylar portion, the first and second sidewalls collectively comprising a first hinge portion;

a tibial component having a bone engaging inferior surface and a bearing engaging superior surface;

a bearing having an articulating inferior surface adapted to articulate along the bearing engaging surface and a superior femoral engaging surface, the bearing having a keyway that defines an opening; and

a yoke having an inferior portion and a superior portion, the superior portion comprising a second hinge portion that hingedly couples to the first hinge portion, the second hinge portion including an axle defining a hinge axis and having an axle post that is movable along the hinge axis between an installation position and an assembled position, the inferior portion configured to at least partially pass through the opening;

wherein the tibial component has a first engagement portion formed thereon including at least one superiorly extending finger having a catch surface that generally opposes the bearing engaging superior surface and wherein the inferior portion of the yoke has a second engagement portion formed thereon including at least one tang having a superior surface that generally opposes the catch surface, wherein the keyway accommodates the at least one tang upon passage of the yoke through the opening of the bearing.

2. The prosthesis of claim 1 wherein the femoral component comprises a bushing on each of the first and second sidewalls, respectively that receive at least portions of the axle in a nested position in the assembled position.

3. The prosthesis of claim 2, further comprising a biasing member that biases the axle post toward the assembled position.

4. The prosthesis of claim 2 wherein in the assembled position the axle extends a distance along the hinge axis that is greater than a distance between the first and second sidewalls of the femoral component.

5. The prosthesis of claim 1, further comprising a hyper-extension stop that selectively couples with the yoke and abuts an intercondylar portion of the femoral component and inhibits hyper-extension of the femoral component relative to the tibial component.

6. The prosthesis of claim 5, further comprising a pin that selectively advances through an opening in the hyper-extension stop and engages the axle and thereby inhibits inferior movement of the yoke.

7. The prosthesis of claim 6 wherein the hyper-extension stop has lateral wings that oppose the first and second sidewalls of the femoral component.

8. The prosthesis of claim 1 wherein the superior surface of the tibial component has a first bi-helical interface and the inferior surface of the bearing has a second bi-helical interface, the first and second bi-helical interfaces cooperating to produce a longitudinal distraction of the femoral component relative to the tibial component during the rotation of the femoral component about the superior/inferior axis relative to the tibial component.

9. The prosthesis of claim 8 wherein the longitudinal distraction is inhibited upon sufficient rotation of the femoral component about the superior/inferior surface such that the catch surface of the finger and the superior surface of the tang abut.

10. The prosthesis of claim 1 wherein the inferior portion of the yoke has a boss that receives a post extending from the bearing engaging surface of the tibial component.

11. The prosthesis of claim 10 further comprising a bushing interposed between the post and the boss of the yoke, the bushing formed of a non-metallic material.

12. The prosthesis of claim 10 wherein the tibial component has an annular channel into the bearing engaging surface between the post and the at least one finger, the annular channel accommodating the at least one tang of the yoke.

13. A prosthesis for replacing a knee joint between a femur and a tibia, the prosthesis comprising:

a femoral component including a first condylar portion, a second condylar portion, a first sidewall extending superiorly from the first condylar portion, a second sidewall extending superiorly from the second condylar portion, the first and second sidewalls collectively comprising a first hinge portion;

a tibial component having a bone engaging inferior surface and a bearing engaging superior surface, the tibial component having a first engagement portion formed thereon including a superiorly extending finger, wherein the superior surface of the tibial component has a first bi-helical interface and the inferior surface of the bearing has a second bi-helical interface, the first and second bi-helical interfaces cooperating to produce a longitudinal distraction of the femoral component relative to the tibial component during the rotation of the femoral component about the superior/inferior axis relative to the tibial component;

a bearing having an inferior surface that engages the bearing engaging surface and a superior femoral engaging surface, the bearing having a keyway that defines an opening; and

a yoke having an inferior portion and a superior portion, the superior portion having an axle that comprises a second hinge portion that hingedly couples to the first hinge portion, the inferior portion having a second engagement portion including a tang, the second engagement portion configured to at least partially pass through the opening to a position wherein the tang generally opposes a portion of the finger, wherein the keyway accommodates the tang upon passage of the yoke through the opening of the bearing.

14. The prosthesis of claim 13 wherein the first and second hinge portions cooperate to inhibit distraction of the femoral component relative to the superior surface of the bearing.

15. The prosthesis of claim 13 wherein the axle has a hinge axis and further comprises an axle post that is movable along the hinge axis between an installation position and an assembled position.

16. The prosthesis of claim 15, further comprising a biasing member that biases the axle post toward the assembled position.

17. The prosthesis of claim 15 wherein in the assembled position the axle extends a distance along the hinge axis that is greater than a distance between the first and second sidewalls of the femoral component.

18. The prosthesis of claim 13, further comprising a hyper-extension stop that selectively couples with the yoke and abuts an intercondylar portion of the femoral component and inhibits hyper-extension of the femoral component relative to the tibial component.

19. The prosthesis of claim 18, further comprising a pin that selectively advances through an opening in the hyper-extension stop and engages the axle and thereby inhibits inferior movement of the yoke.

20. The prosthesis of claim 19 wherein the hyper-extension stop has lateral wings that oppose the first and second sidewalls of the femoral component.

21. A prosthesis for replacing a knee joint between a femur and a tibia, the prosthesis comprising:

a femoral component including a first condylar portion, a second condylar portion, a first sidewall extending superiorly from the first condylar portion, a second sidewall extending superiorly from the second condylar portion, the first and second sidewalls collectively comprising a first hinge portion;

a tibial component having a bone engaging inferior surface, a bearing engaging superior surface and an engagement portion including at least one superiorly extending finger;

a bearing having an articulating inferior surface adapted to articulate along the bearing engaging surface and a superior femoral engaging surface, the bearing defining an opening; and

a yoke having an inferior portion and a superior portion, the superior portion comprising a second hinge portion that hingedly couples to the first hinge portion, the second hinge portion including an axle defining a hinge axis and having an axle post that is movable along the hinge axis between an installation position and an assembled position, the inferior portion configured to at least partially pass through the opening, wherein the inferior portion of the yoke has a second engagement portion including at least one tang, the yoke further including a boss that receives a post extending from the bearing engaging surface of the tibial component and wherein the tibial component has an annular channel into the bearing engaging surface between the post and the at least one finger, the annular channel accommodating the at least one tang of the yoke.

22. The prosthesis of claim 21 wherein the superior surface of the tibial component has a first bi-helical interface and the inferior surface of the bearing has a second bi-helical interface, the first and second bi-helical interfaces cooperating to produce a longitudinal distraction of the femoral component relative to the tibial component during the rotation of the femoral component about the superior/inferior axis relative to the tibial component.