The vast majority of sprained ankles are known medically as lateral inversion sprains. The three major outer ligaments which help hold the bones of the ankle joint in place are stretched or torn when the foot rolls unnaturally to the outside. Swelling - The body attempts to prevent further trauma by immobilizing the area through swelling. The degree of swelling often serves as the first indication of sprain severity. It almost never bothers you, although the ligaments are mildly stretched.
Recovery usually takes place rapidly.
There is definite and fairly rapid discomfort and pain, although the patient will sometimes try and 'walk it off,' often without success. The ligament stretching is definitely more profound, and there may be mild tearing, but surgical repair is not required. Severe - The defining difference between a grade two and grade three sprain is the extent of ligament damage. The tear may be complete, the ligament may be separated from the bone, or the ligament may pull off a bone fragment. Swelling is immediate and pronounced.