If patients have the symptom of crunching when turning the ankle, it may be due to the presence of ligament or tendon injuries, bony blocks and other etiological factors, as follows: First, ligament or tendon injuries: some patients will suffer from old ligament or tendon injuries of the ankle joint, followed by such symptoms. After spraining the ankle joint, these patients often do not take proper treatment, resulting in localized joint instability, or scar adhesion, structural hyperplasia, which will lead to the symptom of rattling when the patient turns the ankle joint. Secondly, bony obstruction: some patients may have such symptoms due to bony obstruction inside the ankle joint, for example, after the patients have fracture of the ankle joint or internal cartilage damage, if the treatment is not complete, it may easily be complicated with traumatic arthritis, or there are free bodies inside the joint, which will cause the symptoms mentioned above.