Medical history and exam by a doctor. X-rays of the lower leg, knee, hip and ankle to rule out fractures. Prolonged healing time if usual activities are resumed too soon. Proneness to repeated injury. If this is a first-time injury, proper care and sufficient healing time before resuming activity should prevent permanent disability.
Ligaments have a poor blood supply, and torn ligaments require as much healing time as fractures.
Follow your doctor's instructions. These instructions are supplemental. See Appendix 1 for details. The doctor usually applies a splint from ankle to groin to immobilize the sprained leg. Put ice chips or cubes in a plastic bag.