The principles of knee rehabilitation for rheumatic diseases are to reduce pain, control inflammation, maintain a good general condition, and prevent or improve functional impairment. The focus of rehabilitation treatment in the acute phase is joint rest, adopting a comfortable position, limiting the activities of the affected joint, avoiding unnecessary injury, maintaining the functional position of the joint as much as possible, avoiding pressure on the painful area, and using a brace to prop up the bed cover. During the recovery period, the main focus is to maintain joint mobility, exercise joint function and correct deformities. Cooperate with rehabilitation training: 1. Isometric contraction exercises for quadriceps muscle in the 1st week. The patient is placed in a supine position with the knee joint straight. Tighten the quadriceps for 8 seconds and relax for 2 seconds. 4 times a week for 10 minutes each time. 2. Continue quadriceps isometric contraction exercises and start straight leg raising exercises in week 2. The patient is supine, the knee on the healthy side is flexed, the knee on the affected side is straightened, the ankle is in a functional position, and the leg is lifted, twice a day for 10 minutes. Hip abduction should be avoided for this exercise, as it may aggravate the pain of the affected knee. 3. In the 3rd week, continue the quadriceps isometric contraction exercises and straight leg raising exercises and start sandbag exercises. According to the condition, add sandbag to the patient’s ankle for straight leg raising exercise, the sandbag weighs 2-3Kg to increase the quadriceps muscle strength. 2 times a day, 10 minutes each time. 4. In the 4th week, while insisting on the above rehabilitation training, you can also do empty pedal bicycle exercises, 10 minutes each time, 2 times a day. Rehabilitation training should be persistent, even lifelong exercise. Exercise according to the above methods, gradually increase the time and intensity of training, and pay attention to the affected limbs to keep warm and avoid trauma stimulation.