Fracture line blurring usually occurs after 4 to 6 weeks for fractures without significant displacement, and may take 6 to 12 weeks for severe fractures to blur. Fracture line blurring is a kind of imaging manifestation of fracture healing, generally the fracture degree is light, the displacement is not obvious fracture, its healing speed is relatively fast, so the fracture line blurring is also earlier than other fracture types, in most cases, the fracture line blurring can be seen in the review 4~6 weeks after the fracture. Such as green branch fracture, cleft fracture. For severe fractures, such as comminuted fractures. Generally due to severe bone destruction and heavy damage to the periosteum and blood supply, the overall healing of the fracture is slower and the fracture line is blurred for a longer period of time. It usually takes 6 to 12 weeks for the fracture line to blur. However, in some cases, due to the condition of the body, surgical fixation and other factors, there are some individual differences in the time of fracture line blurring.