Most of the high instep of the affected limb after external ankle fracture is due to soft tissue swelling caused by trauma and tissue repair. 1. Trauma: most of the external ankle fracture requires surgical treatment such as incision and internal fixation, due to the trauma itself and the unavoidable damage to the soft tissues around the ankle joint during the operation, the venous return is slowed down or blocked in the postoperative period, which causes the swelling around the ankle joint, and the dorsal high phenomenon may appear. 2. Tissue repair: after fracture surgery, due to the rehabilitation training process, the soft tissues are constantly stimulated by pulling, the tissue repair process will be repeated congestion, edema caused by agitation, as well as tissue regeneration, which may also lead to the phenomenon of dorsal height of the affected limb after surgery. There may be other reasons for the high dorsum of the affected limb after the surgery of external ankle fracture, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment under the guidance of the doctor.