Fractures, in part, are caused by external forces that destroy the original bone structure, which in turn causes the bone to be unable to continue to stress, producing local pain or pressure pain, and after the continuity is broken, can cause loss of joint function. Part of it is due to the bone structure itself being invaded by disease, which weakens the bearing capacity of the bone and leads to pathological fracture. In part, it is due to fatigue, such as long runs and long walks, resulting in a fracture called a fatigue fracture. In part, it is a green branch fracture caused by the child’s bones being tougher, after being subjected to violence, i.e. the bone is only deformed more and not completely broken.