In patients with anterior separation of the inferior tibiofibular joint, the external ankle presents a depression on the ankle orthopantomogram, indicating that the fibula is in an externally rotated position, and the fibula should be examined to exclude a fibular fracture. Treatment and prevention of external ankle presenting depression: 1. Non-surgical treatment: If it is a simple tibiofibular joint ligament injury, only closed repositioning and calf cast fixation for 6 weeks is required. For posterior tibial labral avulsion fracture, the fracture fragment does not exceed 1/4 joint surface and has no effect on the joint, it can also be fixed in plaster. In cases with fibula fracture, for example, if the fracture can be repositioned, plaster fixation is still available. If the fracture is not satisfactorily repositioned, the fibula should be repositioned by incision and internal fixation, and after the fibula is firmly fixed, the calf should be fixed in plaster for 6 weeks. 2.Surgical treatment: in the fibula fracture with tibiofibular joint separation, the repositioning treatment of the fibula is very important. According to different fracture types, the corresponding method should be used. (1) If the distal fibula is spiral fracture: it should be fixed with two screws, and the screws should be fixed from the posterior external to the anterior internal and from the distal to the proximal end. (2) Transverse or short oblique fractures of the lower fibula: fixation with an intramedullary nail may be used to ensure stability of the fibula and to maintain joint repositioning of the subtalar fibula. In order to avoid screw breakage and to protect the physiological function of the ankle joint and fibula, the authors advocate removing the screws at the subtalar joint 8 weeks after surgery.