(1) Early stage: within 1-2 weeks after the injury, the injured limb is swollen and painful, and the fracture end is unstable and easily re-displaced. The main purpose of functional training in this period is to promote blood circulation, which is beneficial to eliminate swelling and stabilize the fracture. The main form of functional training is isometric contraction of the affected limb muscles. In other words, on the basis of joint immobility, the muscles of the affected limb will do rhythmic static contraction and relaxation. Both we often say that the force of tensing and relaxation to prevent muscle atrophy or adhesion. (2) Mid-term: 2 weeks after the injury to the clinical healing of the fracture. The swelling of the injured limb gradually disappears, pain is relieved, fibrous joints appear at the fracture end, and bone scabs are gradually formed, and the fracture is stabilized. During this period, in addition to continuing muscle contraction training of the injured limb, the functional activities of the proximal and distal unfixed joints of the fracture and the activities of the upper and lower joints of the fracture can be gradually restored under the guidance of the medical personnel and the healthy limbs, and gradually change from passive activities to active activities, increase active joint flexion and extension activities, prevent muscle atrophy, avoid joint stiffness and reduce functional impairment. If the condition allows, you should get up as early as possible to perform whole body activities. At the same time, physical therapy should be used to reduce swelling, relieve pain, and promote the formation of bone scabs. (3) Late stage: In other words, clinical healing is achieved or external fixation has been removed, bony scabs have been formed, X-ray examination has become visible, and the bone has a certain degree of support. However, most of the adjacent joints have decreased joint mobility, muscle atrophy and other functional disorders. Therefore, the purpose of rehabilitation in this period is to restore the mobility of the involved joints, strengthen the muscles, and restore the limb function. The main form of training is to strengthen the active activities and weight-bearing exercises of the injured limb joints, so that the functions of each joint can be rapidly restored to the normal range of activities and normal strength, and to pay attention to the coordination of the whole body functional training and gait training. At the same time, the training objectives and changes in the condition are combined with physical therapy methods.