The three main principles of fracture treatment are repositioning, fixation, and functional exercise. Functional exercise is what we call rehabilitation, or rehab, which is more accurate and relevant. Specifically speaking of functional exercise, that is, post-operative fracture rehabilitation, we will explain it from the following perspectives. 1.Weight bearing The ability to bear weight is usually determined whether the fracture site is on the force line of the upper and lower extremities, and the fracture on the force line is prohibited to bear weight until the bone scab is formed. When the imaging shows the growth of the bone scab, we can start the gradual weight-bearing training to start the fracture site to receive light stress stimulation to promote the healing of the fracture. For fractures that do not occur in the line of force, our weight-bearing is not a major concern. The clinical healing criteria for fractures give the following answers: (1) No pressure pain at the fracture site and no percussion pain along the longitudinal axis of the limb. (2) No discomfort from self-elevation of the affected limb. (3) No abnormal movement of the fracture when the limb is twisted with appropriate force. (4) X-ray shows blurred fracture line with continuous bone scab passing through the fracture line. (5) After the external fixation is released, the injured limb can meet the following requirements: (1) the upper limb can lift 1 kg of weight forward for 1 minute; (2) the lower limb can walk continuously on the flat ground for 3 minutes and not less than 30 steps without supporting the crutches. (6) Continuous observation for two weeks without deformation of the fracture. (3) and (5) must be measured carefully, and can be practiced for several days and then measured in order not to damage the bone scab to occur re-fracture. Until then, we can use crutches, walkers, etc. to help stand and walk, usually without pain, then there is no problem. The foreign translation is called toe weight-bearing, which can be started from this. 2, pain management In the field of physical therapy we usually use hot and cold wet compresses, wax therapy, infrared light therapy, ultrasonic therapy, interferential electrotherapy and tens to relieve pain, pain is the self-protection of the human body, the pulling pain of contracted muscles and other soft tissues, tearing the joint inside and outside the scar adhesions generated by dull pain, joint effusion leading to swelling pain, sharp pain caused by synovial impaction, etc. are the most common conditions For different types of pain, we choose the appropriate treatment to reduce the pain. 3, strength growth Scientific strength training methods need to choose between open and closed chain movements, centripetal and centrifugal contractions and static contractions. It also involves the relationship between time, intensity and frequency. With the exception of some specific cases, open chain exercises are simple and easy, with low loads, but difficult to initiate during atrophy, while closed chain exercises are more difficult, with high loads, but easy to initiate during atrophy. Large intensity, less number of strength training to increase explosive power; small intensity, multiple sets of strength training to increase endurance. 4, joint mobility increase The big principles: (1) pain-free treatment is the direction of effort, pulling pain is often generated with the treatment, severe pain needs to be avoided. (2) can actively muscle contraction to increase the angle is better than passive activities to increase the angle.