After knee ligament rupture surgery there is a brace for external fixation protection, and with the external fixation protection, you can slowly try to perform small functional rehabilitation exercises with crutches because you have some mobility. After the external fixation brace is removed, a non-weight-bearing to weight-bearing functional rehabilitation process is required. At first, you can lie on the bed and lift your leg up, holding the calf with two hands, so that the calf is as close to the thigh as possible. During this process, the range of motion of the knee joint gradually increases and the surrounding muscles are well exercised. And you can sit on the edge of the bed and use the muscles of the thigh to contract and try to lift the lower leg, which has a part of the effect of weight training. After the range of motion is restored, you can slowly exercise walking on the floor and squatting, which are weight-bearing exercises.