What is Ankle Sprain?
Sprained ankles are the most frequent type of musculoskeletal injury seen by primary-care providers. Ankle sprains are common sports injuries but also happen during everyday activities. An unnatural twisting motion of the ankle joint can happen when the foot is planted awkwardly, when the ground is uneven, or when an unusual amount of force is applied to the joint. The ankle joint is made up of three bones. The tibia: the major bone of the lower leg. It bears most of the body's weight. Its bottom portion forms the medial malleolus, the inside bump of the ankle.The fibula: the smaller of the two bones in the lower leg. Its lower end forms the lateral malleolus, the outer bump of the ankle. The talus: the top bone of the foot. Tendons connect muscles to bones. Several muscles control motion at the ankle. Each has a tendon connecting it to one or more of the bones of the foot.Tendons can be stretched or torn when the joint is subjected to greater than normal stress. Chronic inflammation of a stretched or torn tendon is called tendinitis. Tendons also can be pulled off the bone, called an avulsion injury. Ligaments provide connection between bones. Sprains are injuries to the ligaments. The ankle has many bones that come together to form the joint, so it has many ligaments holding it together. Stress on these ligaments can cause them to stretch or tear. The most commonly injured ligament is the anterior talofibular ligament that connects the front part of the fibula to the talus bone on the front-outer part of the ankle joint.
Ankle Anatomy and Common Injuries