Sprain: An injury to a ligament that results from overuse or trauma. Sprains occurs when there is a stretch or tear in one or more ligaments, slightly elastic bands of tissue that keep the bones in place while permitting movement at a joint. The treatment of a sprain involves applying ice packs, resting and elevating the involved joint, and using anti-inflammatory medications. Depending on the severity and location of the sprain, support bracing can help. Local cortisone injections are sometimes given for persistent inflammation. Activity may be resumed gradually. Ice application after activity can reduce or prevent recurrent inflammation. Occasionally, supportive bracing can prevent reinjury. In severe sprains, orthopedic surgical repair may be performed.