Patellar fractures usually do not injure the nerve, but there are a few cases that may injure the saphenous nerve or superficial peroneal nerve causing the above symptoms. If there is no local cause of injury, then it is recommended to check the lumbar spine, which can be caused by a herniated or bulging lumbar disc compressing the sciatic nerve. Patellofemoral fractures are more common injuries, mostly due to bruises or falls. Treatment usually includes conservative treatment with external fixation in a cast or surgical incision and internal fixation. Treatment of fresh patellar fractures should maximize the smoothness of the joint surface, give a stronger internal fixation, and move the knee early to prevent the occurrence of traumatic arthritis. Rehabilitation care of fracture is an important and indispensable part of the treatment process. It can avoid the occurrence of disuse syndrome of the fracture, such as muscle atrophy of the affected limb, joint stiffness and limb deformity, which is extremely important for patients after the fixed reset of patella fracture. 1, early post-injury pain slightly reduced, that should begin to practice limb quadriceps isometric contraction, not less than 100 times per hour, to prevent limb quadriceps adhesion, atrophy, knee extension weakness, to lay a good foundation for walking on the ground. If there is no contraindication, the patella should be pushed left and right at any time to prevent adhesion of the patella to the joint surface. Practicing ankle and foot joint activities, moving the toes hard, slowly and as widely as possible is important for promoting circulation, decreasing swelling and preventing deep vein thrombosis. 2, one month after the injury, the doctor can decide to start joint mobility exercises according to the situation, otherwise the knee joint may stiffen in the future, affecting the squatting function of the affected limb and causing great inconvenience to life. Exercise methods at home are: 1, sitting on the edge of the bed, the back of the knee pad solid fall do not empty, by others to grasp the power to slowly press down the leg (that is, bending the knee), be sure not to use violence, angle, power to progressively, or put a suitable weight in the back of the foot, such as pillows, etc., their own force to bend the knee, straighten, then bend the knee, straighten the cycle. 2.Lying flat on the bed, the affected limb is straightened and raised perpendicular to the bed, and the knee is flexed and straightened with your own force or with the help of others. 3.Stand on the edge of the bed, hold the edge of the bed with your hand, squat and bend your knee by yourself. It should be noted that: ① the force should be gradual, do not use violence. ② Others help that is called passive training, can only exercise the mobility of the joints, can not exercise muscle strength, and finally rely on their own initiative to exercise, the two should cooperate. ③ pain will occur at the beginning of the exercise, you can take a little painkillers to relieve pain and increase confidence to continue exercising. ④ Do not ask too much of the effect of exercise, that is, do not expect 3-4 days on how, but also can not be used as a reason for negativity. For the joints, stiff joints are useless and a person’s normal life and work will be seriously affected. The knee joint should be flexed to a minimum of about 110 degrees to meet the needs of normal life of a person. The principles of orthopedic treatment are reset, fixation and functional exercise, one of which is indispensable.