The fracture of the lower leg in a three-year-old child, purely from the fracture as well as the age itself, because the shuttle ability of the child in the healing process is very strong, the fracture heals very quickly and can be completely healed in about a month. So the fracture appears and can be treated conservatively by proper manipulation and external fixation of the cast for protection, which basically restores the alignment of the fracture to the line. In some cases, the fracture obviously involves the bone scale, involves the joint surface, and has obvious misalignment, consider surgical repositioning with steel pin fixation. Because of the complications of traumatic arthritis in these areas and the risk of dislocation affecting the growth and development of the child, surgical treatment is the only way to minimize the impact. Therefore, the specific treatment plan should be determined according to the characteristics of the fracture itself.