Foot/Ankle Injuries > Ankle Sprain

The most common type of ankle injury is a sprain that develops as a result of overstretching and/or tearing ligaments (fibrous bands connecting adjacent bones in a joint.) Many ligaments around the ankle can become damaged when the ankle is twisted or forced into a sudden mechanically unnatural position.

The most frequent mechanism for an ankle sprain occurs when weight is applied to the foot on an uneven surface, causing the foot and ankle to roll inward (inversion), or pressure to be placed on the lateral/outside of the foot. Mechanically, because the sole of the foot is pointing inward as force is applied, the ligaments stabilizing the lateral or outside part of the ankle are excessively stressed. Inversion ankle sprains represent 98 percent of all ankle sprains. Many athletes and/or active individuals report hearing a snap or pop at the time of the injury, followed by pain and swelling on the lateral or outside of the ankle.

Degree of Severity of Ankle Sprains

• Grade I – stretch and/or minor tear of the ligament without laxity (loosening)
• Grade II – a more substantial tear of ligament plus some laxity
• Grade III – complete tear of the affected ligament with gross laxity and deformity