An ankle sprain is an injury that causes a stretch or tear of one or more ligaments in the ankle joint.
Ligaments are strong bands of tissue that connect bones at the joint.
Sprains may be classified as mild, moderate, or severe. Most sprains occur on the outside part of the ankle, but they can occur on the inside as well. A sprain is caused by twisting your ankle. Your foot usually turns in or under but may turn to the outside. To diagnose a sprained ankle, the health care provider will review how the injury occurred and consider your symptoms.