The posterior talar triangle is an accessory bone that forms as the posterior ossification center of the talus does not fuse with the rest of the talus during growth. Most posterior talar deltoids do not cause symptoms, but in people who play sports such as soccer, gymnastics, and dance, the need for frequent plantarflexion causes the posterior talar deltoid to become impinged in the limited space of the posterior ankle, resulting in repeated irritation and thus injury, inducing inflammation, leading to pain, and interfering with movement. Longer duration of the disease can also lead to injury of the long flexor tendon of the thumb. An acute violent sprain can also lead to injury to the posterior talus triangle, where the violence is transmitted upward from the heel bone and the posterior articular surface of the heel bone directly impacts the posterior talus triangle. The main pathological basis of posterior talus injuries is degeneration of the articular cartilage surfaces, bone proliferation, necrosis and fracture. Clinical manifestations: There is usually a history of repeated ankle plantarflexion or ankle sprains, with pain in the posterior aspect of the ankle, pronounced on the posterior medial side, aggravated by plantarflexion, walking and exercise, and relieved by rest. Physical examination: Passive plantarflexion can induce posterior ankle pain and localized pressure pain on the posterior medial side. In cases with bunion tendon injury, resistance flexion of the big toe can induce posterior medial ankle pain. Sometimes a posterior medial hard mass can be felt. In severe cases, plantarflexion may be limited. X-rays and CT may reveal an irregular bone mass below the posterior talus, separated from the talus by a narrow gap. MRI may reveal an edematous signal in the posterior talus and surrounding tissues, and an interruption of the normal connection between the talus and the talus. Treatment: Braking, resting, icing, physiotherapy, oral NSAID medication or local seal treatment. Currently, arthroscopic resection of the posterior talar deltoid is used to clean up the local inflammation and the injured thumb long flexor tendon at the same time. The lesion is treated thoroughly, with good surgical results, low complications, traumatic and fast recovery, and has become the preferred option for surgical treatment.