A posteriorly stabilized total knee joint prosthesis comprises a femoral component and a tibial component articulating with each other. The tibial component includes a stabilizing post with a spine articular surface at the posterior thereof. The femoral component has a convex cam follower interacting with the stabilizing post. The convex cam follower configured with a non-cylindrical geometries includes four spine contacting portions gradually extending posteriorly further in order. The last three spine contacting portions define a cam articular surface bearing on the spine articular surface of the post. The cam articular surface has decreasing curvature radiuses along the posterior extension of the cam follower, and the spine articular surface has a concave cam surface with a curvature radius slightly bigger than that of the last spine contacting portion along the extension of the cam follower.
