Ankle sprains are very common injuries and may occur in up to 25,000 people in the United States each day. They may happen during sports and physical fitness activities, or simply by stepping on an uneven surface. A sprained ankle can affect athletes and non-athletes, children, and adults.
Anatomy of the Ankle
[illustration courtesy of the Journal of Musculoskeletal Medicine. © Todd Buck, CMI 2008]
The lateral ankle ligament complex is the most commonly injured site. This is composed of the anterior talofibular, calcaneofibular, and posterior talofibular ligaments.
The anterior talofibular ligament is the most likely component of the lateral ankle complex to be injured in a lateral ankle sprain. Overall, 85% of sprains are inversion (inward) injuries that involve the lateral ligaments, 5% are eversion (outward) sprains that affect the deltoid or medial ligament, and 10% are syndesmotic injuries or “high ankle” sprains.
Grade I ankle sprains, involving stretching of the ligaments, produce a mild degree of swelling. In spite of mild to moderate pain, weight bearing (putting weight on the affected ankle) is possible.
Grade II ankle sprains, involving a partial tearing of the ligament, are recognized by a moderate degree of swelling. During an examination, a doctor may find mild laxity of the ankle, but there is a firm end point with ligaments still intact. Weight bearing is possible but more painful.
Grade III ankle sprains involve a complete tear of the ligament and result in severe swelling. Evidence of instability is noted on examination and weight bearing is usually difficult.
Most ankle sprains do not require surgical intervention. All ankle sprains recover through three phases:
Phase 1 is considered the acute phase. Depending on the grade of ankle sprain, this phase is generally 1-7 days after the injury and the goal is to minimize swelling and progress toward walking. This involves a combination of protection, relative rest, ice, compression, and elevation (also known as RICE). The patient may receive a short-leg cast, a walking boot, or a brace to support and protect the ankle and may require crutches as well. Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen may also be recommended to help reduce pain and inflammation.
Phase 2 is the recovery phase and usually lasts 1-2 weeks, depending on the grade of injury. The goal during this period is to protect the ankle as ligaments heal while beginning to restore function. Therapeutic exercises are initiated and include range of motion, strengthening, and drills to restore proprioception (position sense) and balance.
Phase 3 is the functional phase of rehabilitation and may last weeks to months, depending on the severity of the injury. The goal of this phase is to return to previous level of activity. The ankle should now have full range of motion. Strengthening continues in this phase with advanced, progressive exercises that promote agility and power.
Outcomes following ankle sprains are usually very favorable. However, if the severity of the injury is not recognized and is not treated with the necessary attention and care, chronic problems of pain and instability may result. If pain or a sense of instability persists despite rehabilitation, further evaluation and treatment is needed.
More severe grade III sprains may result in prolonged or permanent ankle pain and instability and may require surgical intervention. Strict adherence to the previously outlined rehabilitation principles will maximize the potential for a complete recovery and return to full activity.