Four months of comminuted fracture of the patella leg stiffness to do rehabilitation is possible to recover. Comminuted fracture of the patella is usually treated with surgery, postoperative rehabilitation, if not carried out in time or poor rehabilitation results will be stiff legs, and can lead to the knee joint internal and external adhesions, ligament contracture and other lesions, thus affecting the joint function, can not be fully flexed the knee. At four months of comminuted patella fracture, the bone healing is usually more solid, at this time for the stiff knee joint, the main patella loosening, joint mobility training, muscle strength training around the knee joint and with physical therapy, if necessary, nerve block joint loosening technology and joint release surgery. Most of the patients can get good progress in knee range of motion through a period of training, and can continue the rehabilitation training until the knee flexion reaches 135°. A small number of patients have poor rehabilitation and require nerve blocks or surgical management. Very few patients ultimately do not recover completely. Comminuted patella fracture requires early, timely and scientific rehabilitation training under the guidance of a doctor to avoid joint stiffness, muscle atrophy and other sequelae.