Quadriceps isometric contraction exercises, squatting horse stance and ball clamping training can be carried out. 1, quadriceps isometric contraction exercises, patients lying on their backs, the affected limbs try to extend the knee, press the bed surface, can feel the thigh muscles tense, keep 15s after relaxation. 2.Squatting horse stance, the two feet stand one and a half shoulder width apart, slowly bend the knee, bend the hip, keep the torso straight, arms naturally stretched out in front, try to squat to the thighs parallel to the ground, keep 15s and then relax. 3, clamp the ball training, patients sitting position, will be a ball clamped on the inside of the two thighs, gradually clamped to the maximum limit of their ability to withstand, keep 15s after relaxation.