Injuries involving the ankle range from the ubiquitous "sprained ankle" to fracture-dislocation injuries which may have permanent effects on athletic performance. In sports involving running and jumping activities, ankle sprains constitute up to 25% of injuries incurred during these activities. In basketball and soccer, 30-45% of injuries involve the ankle, and in soccer, 3/4 of the ankle injuries involve the lateral ligamentous structures.

The most common injuries to the ankle are "sprains", which usually involve stretching, tearing or rupture of the ligamentous structures of the 3 ankle joints.

Most ankle sprain injuries can be classified as "mild", "moderate" or "severe", which roughly correspond with the stretch, tear and rupture categories of ligamentous injuries. When joint dislocation, joint capsule rupture or bone fracture are part of the injury, the classification is always "severe". Because of the mobility of the ankle and the numerous ligaments involved in maintaining this joint's structure, the positioning of the foot and ankle at the time of injury dictate the structures that are injured - all of which may be referred to as "sprained ankle".