Chronic ankle instability is usually caused by repeated ankle sprains and is described as the gradual giving way of the outside of the ankle. Some symptoms of ankle instability include constant inflammation or swelling, tenderness, and instability in the ankle. After a sprained ankle, the ligaments become stretched and torn. Proper rehabilitation is required to strengthen the muscles around the ankle and rehabilitate the tissues within the ankle that affect your balance. In addition, physical therapy, medications, and bracing can help treat chronic ankle instability. Failure to do so may result in repeated ankle sprains, or possibly surgery.