When the foot is smashed, to determine whether the bone is injured, the first point is to observe whether the local abnormal activity is formed, once the abnormal joint activity is formed in the part that should not appear, it means that there must be a fracture. The second point is to observe whether the foot is locally deformed after being smashed, and if a deformity is formed, it means that there is a fracture. The third point, observe whether the foot is smashed, the formation of bone rubbing sound or bone rubbing feeling, once the local formation of bone rubbing sound, or can touch the bone rubbing feeling, indicating that the local fracture must exist. The above three points are the most direct evidence to determine whether the foot was smashed, whether the injury to the bone, there are not obvious fractures, the above several conditions may not appear, and ultimately need to be determined by X-ray.