HIGH PERFORMANCE KNEE PROSTHESES

摘要

Knee prostheses featuring components that more faithfully replicate the structure and function of the human knee joint in order to provide, among other benefits: greater flexion of the knee in a more natural way by promoting or at least accommodating internal tibial rotation in a controlled way, replication of the natural screw home mechanism, and controlled articulation of the tibia and femur respective to each other in a more natural way. In a preferred embodiment, such prostheses include an insert component disposed between a femoral component and a tibial component, the insert component preferably featuring among other things a reversely contoured posterolateral bearing surface that helps impart internal rotation to the tibia as the knee flexes. Other surfaces can also be specially shaped to achieve similar results, preferably using iterative automated techniques that allow testing and iterative design taking into account a manageable set of major forces acting on the knee during normal functioning, together with information that is known about natural knee joint kinetics and kinematics.

主权项

1. A prosthesis for replacement of a least part of a knee joint in a leg, the leg including a femur, a tibia and the prosthesis comprising:
(a) a femoral component adapted to fit on a distal end of the femur, the femoral component comprising:
(i) a lateral condylar structure defining a lateral bearing surface and an anterior portion; and(ii) a medial condylar structure defining a medial bearing surface; (b) an accommodation structure corresponding to a proximal end of the tibia and configured to cooperate with the femoral component, the accommodation structure comprising:
(i) a medial accommodation surface configured to cooperate with the medial bearing surface, the medial accommodation surface comprising a medial posterior edge; and(ii) a lateral accommodation surface configured to cooperate with the lateral bearing surface, the lateral accommodation surface comprising a lateral posterior edge;wherein the medial posterior edge is superior to the lateral posterior edge such that a posterior-most portion of the medial accommodation surface is thicker than a posterior-most portion of the lateral accommodation surface in a superior-inferior direction.