Ankle sprains are common injuries that occur when ligaments are stretched or ruptured. The ankle sprain is the most common athletic injury. Nearly 85% of ankle sprains are on the outside of ankle joint. Many sprains occur when participating in sports, or by twisting the ankle when walking on an uneven surface. Some individuals, due to their bone structure or foot type, are more prone to ankle sprains. Sprains should be treated initially with rest, ice, compression, and elevation. Occasionally a cast will be needed to allow the ligaments to heal properly and prevent further injury.