Abstract: A prosthetic knee joint includes: (a) a femoral member comprising rigid material with a convex, wear-resistant femoral contact surface including a convex ridge; (b) a tibial assembly including: (i) at least one cup comprising rigid material with a body and a rim substantially thicker than the body defining a wear-resistant cup contact surface; (ii) a rigid base; and (iii) a spring support interconnecting the cup and the base, the spring support elastically deflectable permitting controlled pivoting of the at least one cup; (c) wherein the cup contact surface bears against the femoral contact surface, transferring axial and lateral loads between the cup and femoral member, while allowing pivoting between the cup and femoral member; and (d) wherein the at least one cup allows the rim to deform elastically, permitting the cup contact surface to conform in an irregular shape to the femoral contact surface, when the knee joint is loaded.

Abstract: A prosthetic knee joint includes: (a) a femoral member comprising rigid material with a convex, wear-resistant femoral contact surface including a convex ridge; (b) a tibial assembly including: (i) at least one cup comprising rigid material with a body and a rim substantially thicker than the body defining a wear-resistant cup contact surface; (ii) a rigid base; and (iii) a spring support interconnecting the cup and the base, the spring support elastically deflectable permitting controlled pivoting of the at least one cup; (c) wherein the cup contact surface bears against the femoral contact surface, transferring axial and lateral loads between the cup and femoral member, while allowing pivoting between the cup and femoral member; and (d) wherein the at least one cup allows the rim to deform elastically, permitting the cup contact surface to conform in an irregular shape to the femoral contact surface, when the knee joint is loaded.