BackgroundThe ankle joint experiences more weight per unit of area than any other joint in the body. Ankle injuries are among the most common reasons for visits to clinics and emergency rooms. The most common mechanism of injury at the ankle is twisting or rotation, which usually involves inward twisting (inversion) of the foot at the ankle joint. Commonly an inversion injury will produce a sprain of the ligaments of the ankle or a bony fracture. The most common types of injuries of the ankle include:
- Sprain - Sudden over-stretching that causes damage to the ligament is a sprain. "Sprain" should not be confused with "strain".
- Strain - The over-stretching of a muscle causes a strain.
- Dislocation - A dislocation is the displacement of bones at a joint from a normal position.
- Fractures - A fracture is simply defined as the breakage of a bone.
The AnatomyThe coming together of the large lower leg bones (tibia and fibula) and anklebones (primarily the talus) make up the ankle joint. The anatomy of the ankle is often thought of as a simple hinge joint. However, it is more accurately thought of as a saddle joint in which the bones in the ankle are stabilized by the presence of ligaments. Ligaments attach bones together and at the ankle joint prevent sideways sliding of the bones. The names of the ligaments surrounding the ankle include the calcaneotibial and the anterior- and posterior talofibular ligaments. The strongest ligament at the ankle is the deltoid ligament, which lies on the medial side of the ankle (the side facing the opposite ankle). The motion at the ankle includes only flexion and extension (upward and downward movement).
Sprains and StrainsSprains are the most common injuries of the ankle, and the ligaments that surround the ankle joint are the most commonly injured ligaments in the body. There are three levels of severity of sprains. Grade 1 refers to simple over-stretching of the ligaments without any structural damage, grade 2 refers to partial tearing of the ligament, and grade 3 happens when there is complete tearing of the involved ligament. Usually an inversion (inward rotation) injury will produce a sprain of the ligaments at the ankle. A similar injury can occur as the result of outward rotation (eversion). Eversion involves over-stretching of the deltoid ligament, which is very strong and unlikely to sprain; therefore, instead of a sprain severe eversions result in fracture of the bones that are held together by the deltoid ligament. The most common symptoms of sprain are pain, tenderness, and swelling in the area of ligament damage. Bruising (contusion) may also occur. Contusion is the result of damage to the blood vessels and is usually not significant. Loss of function at the ankle may also be present. X-rays should be done to rule out the existence of a fracture.
Strains are muscular injuries that are caused by virtually the same mechanisms as sprains; they, however, signify a more serious injury.
Ankle sprains are usually treated conservatively. Initial treatments of elevation and icing the area (for about 15 minutes three to four times a day) are helpful. The treatment regimen, commonly known to physicians and sports trainers as "RICE" (Rest, Ice, Compression, and Elevation) is often used. Compression is usually accomplished by wrapping the ankle firmly with an elastic wrap. This treatment is usually done for several days. Anti-inflammatory medications (For example, you can buy ibuprofen.) and pain medicines (such as Tylenol) may be helpful in improving pain and minimizing discomfort. Sprains tend to recur, and for that reason it is important to strengthen the ankle joint by exercising the muscles and ligaments of the ankle regularly. To prevent injuries, athletes should wrap their ankles prior to sporting activities, especially those with prior ankle injuries. Strains are treated conservatively with rest, ice, and pain medications.