Knee active limb exercise, the main methods are as follows: 1, heel and hip exercise method: the patient kneeling on the bed, the upper body upright, the hips as far down as possible to sit, so that the heel and hip contact, in order to increase the knee flexion range of the knee joint. In conjunction with the pushing knee flexion and stretching method. 2, suspension pedaling method: patient supine position, lower limbs suspended, like pedaling a bicycle alternately upward pedaling air relaxation. 3, quadriceps contraction exercise: supine bed, knee straight, the quadriceps muscle will automatically isometric contraction, a moment later relaxed, so repeated 20 to 30 times. 4, leg press exercise method: stand, legs slightly apart, in the quadriceps do not contract, try to put the knee in the straight position, then lean forward, two upper limbs straight, try to touch the toes with both hands, so repeatedly. 1, 2, 3 method is mainly used to strengthen the quadriceps muscle strength and restore the stability of the knee joint. Functional exercises for the knee joint and quadriceps muscle can enhance the strength of the quadriceps muscle, which can increase the stability of the knee joint. Improve the function of the knee joint. Relieve joint pain caused by joint instability.