A knee joint prosthesis is disclosed. The prosthesis has a femoral component and a tibial component. The tibial component has a tibial plateau element fitted in a tibial tray element. A hemi capstan shaped bridge member is provided between replicated condyles on the femoral component. A specially shaped post is provided between kidney shaped meniscal depression on the tibial plateau element. The bridge member and the post act together to form an additional joint for load transfer during deep flexion of the prosthesis in its operative configuration.