Straighten the knee joint when lying down and when walking. In bed with the lower leg elevated and the toes pointing upward, the knee is suspended and straightened This will reduce swelling and prevent adhesions. If posterior pain is more pronounced you can change position and flex slightly. After surgery, you can use crutches to get down to the ground, but try to stay off the ground on the affected side. It is important to walk as little as possible. Early postoperative walking is not considered exercise, but can cause swelling and fluid accumulation in the knee joint, which can affect the healing of the ligaments and future gait. If meniscal repair sutures are also performed, it is also important to delay or reduce grounding and to use crutches more often. After 2-3 days, you can do the “quadriceps isometric contraction” to exercise the front of the thigh. After 2-3 days, you can do the “quadriceps isometric contraction” to exercise the quadriceps in front of the thigh, alternating between tensing and relaxing exercises. Requirements in the premise of not increasing pain as much as possible to do more than 500 times a day. Can also do “N cord muscle isometric exercise”, is to use the heel and calf at the same time downward pressure on the bed, or the pillow under the leg, downward pressure to keep the leg straight, but also greater than 50 times a day. The “straight leg raise exercise” can be carried out after the isometric contraction exercise is comfortable and pain is not obvious, at first the number of times is not required, as long as you can adhere to a few times, gradually increase. In addition, side leg raises and back leg raises can also be performed. After one week, active and passive knee flexion exercises can be performed. Sit on the edge of the bed and slowly lower the affected leg by gravity, with the muscles of the affected leg completely relaxed, either with the help of a second person or by supporting yourself with your healthy leg. Initially, there may be swelling of the calf and darkening of the skin, so lie flat again and raise the calf when you feel discomfort. Active flexion training can be started after the swelling and pain are significantly reduced. The patient is placed in a flat position, keeping the heel of the foot off the bed, and gradually flexes the knee joint, then relaxes it and repeats it several times, but does not actively straighten the knee joint from the flexed position. During the first month, joint movement beyond 90 degrees is not required. After active and passive exercises of the knee joint, ice packs are required, usually for 15-20 minutes, to bring down the local temperature and reduce swelling and bleeding.