The best time to take radiographs of a rib fracture is at the time of the injury, and about two weeks after the injury, as follows: First, radiographs taken at the time of the rib injury can clarify the location of the rib fracture and the extent of the fracture. If the fracture is not clearly dislocated, only cracked, and occurs in the lateral or posterior ribs, it is usually not easy to detect by radiographs. Secondly, if the rib fracture is so well located that it cannot be detected at the time of injury, it can be treated first, and after two weeks there is bone resorption at the broken end of the fracture, and then X-rays are taken, which can clarify the diagnosis of the rib fracture. Therefore, if the rib fracture cannot be confirmed, treatment can be carried out first, and the diagnosis can be clarified by reviewing the X-ray film regularly, and the normal treatment of rib fracture will not be delayed at the same time.