Totally posterior stabilized knee prosthesis

Abstract

A posterior stabilized knee prosthesis includes a femoral component formed by medial and lateral condyles, each having an anterior portion, a distal portion and a posterior portion, an anterior patella flange interconnecting the anterior portions of the medial and lateral condyles in parallel, spaced apart relation, and a cam member connected to the lateral surface of the posterior portion of the medial condyle and to the medial surface of the posterior portion of the lateral condyle and having a convex cam surface; a tibial component including a multi-radius medial and lateral tibial plateau bearing surfaces for receiving the medial and lateral condyles for rolling and sliding movement thereon, and a follower member positioned between the medial and lateral tibial plateau bearing surfaces for receiving the cam surface for rotational and sliding movement thereon; the cam surface being in contact with the follower member for substantially the entire flexion range of the knee, with the cam surface being in congruent contact with the follower member from approximately the end of posterior rollback at approximately 25.degree.-30.degree. of flexion to full-flexion; and the cam surface being in sliding contact with the follower member to provide the posterior rollback of the convex cam surface during flexion, starting at approximately -6.degree. (hyperextension) of flexion and ending at approximately 25.degree.-30.degree. of flexion; and the cam member and follower member having heights which are not greater than the thickness of the condyles so as not to extend beyond the inner surfaces thereof.

Dependencies are inferred from the claim text.