The fracture of the left external ankle is usually not serious, but if it produces traumatic arthritis, it is more serious, the details are as follows: First, for most of the left external ankle fracture displacement is usually not obvious, even if mild displacement occurs, it can be restored through manual repositioning and external fixation of plaster, and the fracture will not cause obvious impact on the ankle joint after healing, so it is not serious. Secondly, a comminuted left external ankle fracture, or even an external ankle fracture combined with distal tibiofibular joint separation and displacement, is more serious and can easily cause traumatic joint, as well as ankle instability. After the fracture heals, the patient will suffer from severe ankle pain, limited movement and chronic swelling, which will seriously affect the patient’s normal life, work and sports. Therefore, the severity of the left ankle fracture should be judged according to the type of fracture, and timely treatment to restore the flatness of the joint surface as much as possible can reduce the sequelae.