Sprains and strains
A sprain is a complete or incomplete tear in the supporting ligaments surrounding a joint that usually follows a sharp twist. A strain is an injury to a muscle or tendinous attachment. Both usually heal without surgical repair.
Sprains occur when there is trauma to the joint, causing the joint to move in a position it wasn’t intended to move. Strains may be caused by excessive physical effort or activity, improper warming up before an activity, or poor flexibility.
Signs and symptoms
Sprains and strains cause varying signs and symptoms.
A sprain causes local pain (especially during joint movement), swelling, loss of mobility (which may not occur until several hours after the injury), and a black-and-blue discoloration from blood extravasating into surrounding tissues. A sprained ankle is the most common joint injury.