Orthopaedic implant system with hinge

Patent metadata

Field	Value
Publication number	US-12042391-B2
Application number	US-202016863156-A
Country	US
Kind code	B2
Filing date	Apr 30, 2020
Priority date	May 8, 2019
Publication date	Jul 23, 2024
Grant date	Jul 23, 2024

Abstract

An orthopaedic prosthesis includes a tibial tray, a tibial insert configured to be coupled to the tibial tray, a hinge component configured to be received in a passageway of the tibial tray, and a femoral component configured to articular with the tibial insert. The hinge component includes a pair of hinge arms, each of which includes an axle extending therefrom that is configured to be received in an aperture of a corresponding sidewall of an intercondylar compartment of the femoral component. The axles of the hinge arms may be coaxial or non-coaxial. Additionally, each axle may be coaxial with or offset from a center of a constant radius of curvature that defines an articular surface of a corresponding condyle of the femoral component. The axles may have an outer surface of various shapes depending on the embodiment.

First claim

The invention claimed is:

1. An orthopaedic prosthesis comprising:
a tibial tray having a platform configured to be coupled to a surgically-prepared surface of the proximal end of a tibia and a stem extending inferiorly from a bottom surface of the platform, wherein the stem includes a longitudinal internal passageway;
a tibial insert configured to be coupled to the platform, wherein the tibial insert includes a pair of articular surfaces and an aperture defined between the pair of articular surfaces;
a hinge component comprising (i) an elongated shaft configured to be received through the aperture of the tibial insert and into the longitudinal internal passageway of the tibial tray, (ii) a medial hinge arm extending superiorly from a superior end of the elongated shaft and having a medial axle extending medially therefrom, and (iii) a lateral hinge arm extending superiorly from the superior end of the elongated shaft and having a lateral axle extending laterally therefrom;
a femoral component configured to be coupled to a surgically-prepared surface of the distal end of a femur, the femoral component having (i) a pair of spaced apart condyles configured to articulate on the articular surfaces of the tibial insert and (ii) an intercondylar compartment defined between the pair of spaced apart condyles, wherein the intercondylar compartment includes a medial side wall having an aperture defined therein and a lateral side wall having an aperture defined therein,
wherein the medial axle of the medial hinge arm is configured to be received in the aperture of the medial side wall of the intercondylar compartment and the lateral axle of the lateral hinge arm is configured to be received in the aperture of the lateral side wall of the intercondylar compartment.

2. The orthopaedic prosthesis of claim 1 , wherein the pair of hinge arms are moveable toward each other to allow insertion of the pair of hinge arms into the intercondylar compartment of the femoral component.

3. The orthopaedic prosthesis of claim 1 , wherein each of the medial axle and the lateral axle is cylindrical.

4. The orthopaedic prosthesis of claim 1 , wherein the medial axle and the lateral axle are coaxial with each other and cooperate to define a rotation axis about which the femoral component is configured to rotate in an anterior-posterior direction during articulation on the articular surfaces of the tibial insert.

5. The orthopaedic prosthesis of claim 4 , wherein the tibial insert is configured to rotate on the platform in a medial-lateral direction about an axis defined by the stem of the platform.

6. The orthopaedic prosthesis of claim 4 , wherein the pair of spaced apart condyles of the femoral component includes a medial condyle having a medial articular surface defined by a first constant radius of curvature and a lateral condyle having a lateral articular surface defined by a second constant radius of curvature, and
wherein the rotation axis defined by the medial axle and the lateral axle is coaxial with the center of the first constant radius of curvature and with the center of the second constant radius of curvature.

7. The orthopaedic prosthesis of claim 4 , wherein the pair of spaced apart condyles of the femoral component includes a medial condyle having a medial articular surface defined by a first constant radius of curvature and a lateral condyle having a lateral articular surface defined by a second constant radius of curvature, wherein a center of the first constant radius of curvature is coaxial with a center of the second constant radius of curvature to define a curvature axis, and
wherein the rotation axis defined by the medial axle and the lateral axle is posteriorly offset from the curvature axis to cause posterior movement of the femoral component, relative to the tibial insert, during flexion of the orthopaedic prosthesis.

8. The orthopaedic prosthesis of claim 7 , wherein the rotation axis defined by the medial axle and the lateral axle is posteriorly offset from the curvature axis by a distance of five to seven millimeters.

9. The orthopaedic prosthesis of claim 7 , wherein the medial side wall of the intercondylar compartment includes (i) a first aperture configured to receive the medial axle of the medial hinge arm and (ii) a second aperture configured to receive the medial axle and posteriorly offset from the first aperture, and
wherein the lateral side wall of the intercondylar compartment includes (i) a first aperture configured to receive the lateral axle of the lateral hinge arm and located coaxially with the first aperture of the medial side wall and (ii) a second aperture configured to receive the lateral axle and located coaxially with the second aperture of the medial side wall.

10. The orthopaedic prosthesis of claim 1 , wherein the medial axle and the lateral axle are non-coaxial with each other.

11. The orthopaedic prosthesis of claim 10 , wherein the elongated shaft of the hinge component includes a medial elongated shaft component and a lateral elongated shaft component separate from the medial elongated shaft component,
wherein the medial hinge arm extends superiorly from a superior end of the medial shaft component and the lateral hinge arm extends superiorly from the lateral shaft component, and
wherein the medial axle defines a first axis and the lateral axle defines a second axis that is non-coaxial with the first axis.

12. The orthopaedic prosthesis of claim 11 , wherein the pair of spaced apart condyles of the femoral component includes a medial condyle having a medial articular surface defined by a first constant radius of curvature and a lateral condyle having a lateral articular surface defined by a second constant radius of curvature,
wherein the first axis defined by the medial axle is coaxial with a center of the first constant radius of curvature, and
wherein the second axis defined by the lateral axle is posteriorly offset from a center of the second constant radius of curvature to cause posterior movement of the lateral condyle of the femoral component, relative to the medial condyle, during flexion of the orthopaedic prosthesis.

13. The orthopaedic prosthesis of claim 12 , wherein the second axis defined by the lateral axle is posteriorly offset from the center of the second constant radius of curvature by five to seven millimeters.

14. The orthopaedic prosthesis of claim 12 , wherein the medial axle has a hemispherical outer surface and the lateral axle has a hemispherical outer surface having a diameter that is less than a diameter of the hemispherical outer surface of the medial axle, and
wherein the aperture of the lateral side wall of the intercondylar compartment of the femoral component has a diameter less than a diameter of the aperture of the medial side wall of the intercondylar compartment.

15. The orthopaedic prosthesis of claim 14 , wherein the aperture of the medial wall is configured to move posteriorly on the hemispherical outer surface of the medial axle and the aperture of the lateral wall is configured to move anteriorly on the hemispherical outer surface of the lateral axle during flexion of the orthopaedic prosthesis.

16. An orthopaedic prosthesis comprising:
a tibial tray having a platform configured to be coupled to a surgically-prepared surface of the proximal end of a tibia and a stem extending inferiorly from a bottom surface of the platform, wherein the stem includes a longitudinal internal passageway;
a tibial insert configured to be coupled to the platform, wherein the tibial insert includes a medial articular surface, a lateral articular

Assignees

• Depuy Synthes Products Inc

Inventors

• White Stephen E

Classifications

• A61F2/389

  Tibial components (A61F2/3868 takes precedence) · CPC title

• A61F2/3859

  Femoral components · CPC title

• A61F2002/3863

  Condyles fitted on an anchored base · CPC title

• A61F2002/30378

  Spherically-shaped protrusion and recess · CPC title

• A61F2/385 Primary

  also provided with condylar bearing surfaces · CPC title