The criteria for fracture repositioning must first eliminate separation and rotational displacement of the fracture site. The presence of soft tissue at the fracture end after separation and displacement can seriously affect fracture healing and even lead to non-union of the fracture end. Rotational displacements, when they occur, can result in the loss or partial loss of function of the entire limb. For lower extremity fractures, the standard for repositioning is to allow for shortening deformities of up to 1 cm in adults and up to 2 cm in children, which can be gradually corrected during later growth and development. For angulation of the fracture end, mild angulation deformity can be allowed if it is the same as the joint direction activity. However, if the angle is perpendicular to the joint activity, it needs to be corrected gradually. For fractures of the long diaphysis, the alignment and alignment should be at least 1/3 or more; while for fractures of the diaphysis, the alignment and alignment should be at least 3/4 or more.