High Performance Knee Prostheses
3 Assignments
0 Petitions
Accused Products
Abstract
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.
-
Citations
54 Claims
-
1-37. -37. (canceled)
-
38. A knee prosthesis comprising:
-
(a) a femoral component configured to fit on a distal end of a femur, the femoral component comprising an anterior portion, a posterior portion, and a distal portion connecting the anterior portion to the posterior portion, wherein the distal portion includes a medial articular portion and a lateral articular portion, wherein the femoral component further comprises a posterior cam wherein the posterior cam is asymmetric such that a lateral portion of the posterior cam is larger than a medial portion of the posterior cam; (b) a tibial articular component configured to fit on a proximal end of a tibial, the tibial articular component comprising a medial articular surface for articulating with the medial articular portion of the femoral component, and a lateral articular surface for articulating with the lateral articular portion of the femoral component. wherein, when the femoral component is positioned on the tibial articular component in a position and orientation corresponding to approximately zero degrees of flexion, a line extending from a center of contact between the medial articular portion of the femoral component and the medial articular surface of the tibial articular component to a center of contact between the lateral articular portion of the femoral component and the lateral articular surface of the tibial articular component is oriented at an angle of approximately 3 degrees from a line that is generally parallel to a distal internal surface of the femoral component. - View Dependent Claims (39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54)
-
Specification