A knee joint prosthesis is configured to move between an extended position and a flexion position. The knee joint prosthesis includes a femoral component configured to be mounted to a femur, and a tibial component configured to be mounted to a tibia. The tibial component is configured to engage the femoral component to form the knee joint prosthesis. A post is fixedly connected to one of the femoral component and the tibial component, and a cam recess is defined on the other of the femoral component and the tibial component. The cam recess is configured to engage the post in either the extended position or the flexion position of the knee joint prosthesis. An artificial ligament is fixedly connected to the femoral component and the tibial component to simulate either an anterior cruciate ligament or a posterior cruciate ligament.