Patellar joint instability rehabilitation exercise to improve quadriceps strength as the main goal, the method has straight leg raise, resistance knee extension, squatting against the wall, squatting, squatting, deep squatting and so on. 1. Straight leg raise: lie flat on the yoga mat, bend one leg, straighten the other leg to do the lifting action, the position of the force is located in the front side of the thigh inward, and the legs are exchanged. 2. Weighted resistance knee extension: sitting on a chair, upright upper body, a leg does not move, the affected side of the ankle can be tied sandbags, elastic band, complete the leg straightening action, the front side of the thigh force, 10 to 15 groups per day. 3. Squatting against the wall: upright upper body close to the wall, do squatting action, thighs parallel to the ground and calves into 90 °, 1 minute for 1 group, can do 5 groups. 4. Arrow squat: hands pinched waist, upper body straight, one leg forward followed by squatting, thighs before and after the side and hip force, bilateral thighs and calves into 90 °, 10 ~ 20 for a group, 5 groups a day. 5. deep squat: legs shoulder width, natural standing, and then squat, 10 ~ 20 for a group, 5 groups per day. It is recommended that patients go to the regular hospital in a timely manner, under the guidance of the doctor for standardized treatment, so as not to delay the condition.