One of the common diseases of the ankle joint, it refers to a disorder in which friction occurs within the ankle joint or between the tissues surrounding the joint from various causes, producing pain. The disorder can either be caused by or result from altered ankle biomechanics and includes both bony impingement and soft tissue impingement. Bony impingement syndromes include soccer ankle and posterior talar triangle injuries; soft tissue impingement was only discovered after arthroscopy was used in clinical practice. In an inversion sprain or posterior rotation sprain of the ankle joint, the external ankle ligament, as well as the inferior anterior tibiofibular ligament and its distal bundle, receive inversion stress strain and rupture, and the anterolateral joint capsule also tears. Repeated sprains or sports may cause the torn ligament to become embedded in the anterolateral sulcus, and the torn ligament may undergo hyperplasia, hypertrophy, and scar formation during the healing process. The impingement of the aforementioned tissues within the lateral sulcus causes inflammatory hyperplasia of the surrounding synovial membrane, resulting in localized swelling and pain. External rotation or valgus sprains can cause anteromedial impingement syndrome by tearing the medial ankle ligament and medial joint capsule. Depending on the site of injury, ankle impingement syndrome can be classified as follows: 1. Anterolateral impingement syndrome: Posterior ankle rotation injuries usually result in tears of the anterior talofibular ligament, the heel-fibular ligament, and the anterolateral joint capsule. If not treated properly, the inflammatory response at the site of the ligament tear can persist for a long time, resulting in the formation of scar tissue or hypertrophy of the synovial membrane. Because the inflammatory tissue resembles the meniscus of the knee under the arthroscope, it is also known as a “meniscus-like injury”. Medial impingement syndrome: Injury to the external or internal ankle joint can lead to tearing or compression of the deltoid ligament, local scarring or hypertrophy of synovial tissue, which can cause pain when the ankle joint is plantarflexed and turned inward, embedded between the posterior edge of the medial ankle and the medial wall of the talus. 3. Anterior impingement syndrome: It is usually a bony impingement, most commonly caused by the impingement of the anterior border of the talar neck or the distal tibial joint. 4. Posterior impingement syndrome: Bony impingement is common, e.g., talar triangular bone injury, overgrowth of the talus or heel posterior process. Ectopic muscles, such as the 4th peroneal muscle, heel peroneal intrinsic muscle and other soft tissues can also cause posterior impingement syndrome. The soft tissues that cause impingement syndrome are usually hypertrophic, disorganized fibrous scar tissue. The bony structures that cause impingement are hyperplastic bony bulges, and the surrounding synovial and bursal tissues often show inflammatory hyperplasia and congestion. Patients usually have a history of ankle sprains and pain at the site of injury, which can be caused by specific movements and may be accompanied by a “flaccid” sensation. Symptoms are worse after exercise and may be partially relieved by rest. There is pressure pain in the joint space corresponding to the injury site. Pain may be induced by passive plantar flexion/dorsiflexion of the ankle in combination with inversion/extension. The examination includes ankle x-ray and MRI, which are used to diagnose osseous impingement syndrome; MRI can show the site and cause of impingement, as well as identify the presence of articular cartilage damage. Conservative treatment: includes rest, oral NSAIDs, physical therapy, local closure and rehabilitation. Surgical treatment: Arthroscopic surgery consists of debridement of the synovial membrane and the soft tissue masses causing the impingement. Arthroscopic surgery is effective for simple soft tissue impingement syndrome of the ankle joint. In cases of combined chronic instability of the ankle joint, reconstruction of the ligaments is required to restore the stability of the joint during surgery.