The back of the foot is sprained and swollen, it must be clear whether the sprain is accompanied by a fracture, so first take X-rays and reduce the swelling as follows: a. With a fracture: If it is clear that there is a fracture, cast braking should be carried out, and then the lower limb should be elevated so that the swelling can be eliminated the fastest, which is conducive to the return of blood to the swollen part of the limb. If the fracture is displaced and the alignment is poor, surgery should be performed to restore the alignment of the fracture in order to eliminate the swelling the fastest. Second, there is no fracture: If no fracture is observed in the X-ray taken at that time, elastic bandage fixation can be carried out, while walking on the ground should be prohibited, and the foot should be elevated during the fixation period, which is conducive to the reduction of swelling. Generally, for simple soft tissue injury, the period of swelling decreases in about two weeks.