The present invention comprises an implantable knee prosthesis for the arthritic, aging, ligament-deficient knee having a femoral component, a tibial component and patella component forming three interactive knee compartments mainly the lateral, medial, and femoral patellar compartments articulating together with a variable axial pivot type of knee motion. This novel design accomplishes this motion pattern with four femoral component radii coacting with four reciprocal proximal tibial surface recesses. This occurs in a laterally congruent axial pivot fashion during the first half of knee flexion creating efficient external femoral rotation to align the femoral-patellar groove with the patella/quadriceps muscle complex.
