Patent ID: 8206451

Claim:
An orthopaedic knee prosthesis comprising: a tibial bearing configured to be coupled to a tibial tray, the tibial bearing having (i) a platform including a medial bearing surface and a lateral bearing surface and (ii) a spine extending upwardly from the platform between the medial bearing surface and the lateral bearing surface, the spine having a posterior side including a concave cam surface and a convex cam surface, the concave cam surface being concavely curved in the sagittal plane and the convex cam surface being convexly curved in the sagittal plane; and a femoral component configured to articulate with the tibial bearing, the femoral component including (i) a pair of spaced apart condyles defining an intracondylar notch therebetween and (ii) a posterior cam positioned in the intracondylar notch defined between the spaced apart condyles, the posterior cam including a concave cam surface and a convex cam surface that are positioned toward a posterior side of the femoral component, the concave cam surface being concavely curved in the sagittal plane and concavely curved in the medial-lateral direction and the convex cam surface being is convexly curved in the sagittal plane and concavely curved in the medial-lateral direction, wherein the concave cam surface of the posterior cam initially contacts the convex cam surface of the spine during a first range of flexion and the convex cam surface of the posterior cam initially contacts the concave cam surface of the spine during a second range of flexion that is different from the first range of flexion.