Introduction
An ankle sprain is a common injury and usually results when the ankle is twisted, or inverted. The term "sprain" signifies injury (below) to the soft tissues, usually the ligaments, of the ankle. An ankle sprain is a common injury and usually results when the ankle is twisted, or inverted. The term "sprain" signifies injury (below) to the soft tissues, usually the ligaments, of the ankle.

Anatomy
A ligament is made up of multiple strands of tissue - similar to a nylon rope. A sprain results in tearing of the ligaments (right). The tear can be a complete tear of all the strands of the ligament or a partial tear, where a portion of the strands of the ligament are torn. The ligament is weakened by the injury - how much depends on the degree of the tear. The lateral ligaments (below) are by far the most commonly injured ligaments in a typical inversion injury of the ankle.

       

On the lateral side of the ankle there are three ligaments (below) that make up the lateral ligament complex. These include the anterior talofibular ligament (ATF), the calcaneofibular ligament(CF) and the posterior talofibular ligament (PTF). The very common inversion injury to the ankle usually injures the anterior talofibular ligament and the calcaneofibular ligament. The ATF ligament keeps the ankle from sliding forward and the CF ligament keeps the ankle from rolling over on its side.

Symptoms
Initially the ankle is swollen, painful, and may turn echymotic (bruised). The bruising, and the initial swelling, is due to ruptured blood vessels from the tearing of the soft tissues. Most of the initial swelling is actually bleeding (.avi movie) into the surrounding tissues. This initial swelling due to bleeding then increases due to edema fluid leaking into the tissues as well over the next 24 hours.

Diagnosis
The diagnosis of an ankle sprain is usually made by examination of the ankle and xrays to make sure that there is no fracture of the ankle. If there is a complete rupture of the ligaments suspected, your doctor may order stress xrays (below) as well. These xrays are taken while someone twists or "stresses" the ligaments.

    

Medical Treatment
Treatment begins initially by:
·  controlling swelling
·  controlling pain
·  controlling weight bearing
·  Elevation will help control the swelling
·  Gentle compression and ice will control swelling
·  Mild pain relievers will help with the pain
·  Crutches will prevent weight bearing.

Casts have fallen out of favor, and as treatment progresses, early weight bearing (right) has been shown to be beneficial. Braces that can be worn to support the ankle - but still allow weight bearing are the most popular treatment method today. Healing of the ligaments usually takes about 6 weeks. The swelling may be present for several months. A physical therapist may be suggested to help you regain full function of your injured ankle. (See rehabilitation below)

Ankle Instability
In a small number of cases, the ligaments will not heal back as strong as normal. This results in an ankle that is unstable and has a tendency to give away, or twist again very easily. Ankle instability (right) can lead to an ankle that is sore and painful, sometimes swollen, and untrustworthy on rough terrain. If your ankle ligaments do not heal back adequately following an ankle sprain there are several things that may be suggested by your doctor.

A physical therapy program (below) may help strengthen the muscles around the ankle to help make the ankle more reliable. The therapy is also necessary to "retrain" the proprioceptive nerves around the ankle that have been torn with the ligament. These nerves are important in telling our brains how to use the muscles to allow the joints to properly function. An ankle brace may also help control some of the instability and prevent the ankle from giving way.

Surgery
If all these simple measures fail, surgery may be suggested to reconstruct the ligaments that have been torn. Surgery involves making an incision (left) on the side of the ankle. A portion of the tendon (.avi movie) called the peroneus brevis is used to reconstruct the lateral ligaments.

A drill hole is made in the fibula, near the attachment the original ligament. A second drill hole is made in the area where the ligaments attached to the talus. The tendon graft (.avi movie) is then woven these holes to recreate the ligament complex.

After surgery, you will usually be placed in a cast or brace for about 6 weeks to allow the tendon reconstruction to heal. Following removal of the cast, physical therapy will be required to regain full use of the ankle.

Rehabilitation
Whether you have had an ankle sprain that did not require surgery or whether you are recovering form surgical reconstruction of the ankle ligaments you will probably benefit from physical therapy. Your physical therapist will evaluate your foot and ankle on your first visit to therapy. This will enable your therapist to locate the sore tissue and to develop a treatment plan.

The outside ligaments of the ankle are hurt most often in an ankle sprain. This is because most ankle sprains are from an inward twist (an inversion injury). When this happens, the force from the twist may also compress the tissues on the medial, or inside, of the ankle. This can be a source of pain and inflammation on the inside area of the ankle. A grade of I, II, or III is usually given depending on whether you had a slight sprain (I), significant tearing and bleeding (II), or a complete rupture of the tendon (III).

ACUTE TREATMENT
Treatment may vary depending on which grade sprain you've had. In each case, the first line of treatment is to calm the inflammation and halt the swelling. The RICE principle can help address each of these needs.

Rest : A brace or splint will keep the ankle in a safe position, helping you avoid more strain to the sore area. In severe cases, you may require a pair of crutches to limit weight through the foot.

Ice : Cold therapy in the form of ice towels, bags, or wraps can aid in slowing the inflammatory process and in limiting pain. Apply as directed by your therapist.

Compression : An elastic wrap or an air-type brace can compress the sore area, keeping the swelling to a minimum.

Elevation : Keep your ankle elevated above the level of your heart. This will help drain the extra fluid (edema) back into the lymph system.

Other treatment choices may be used to further limit pain and inflammation. Examples include contrast baths with hot and cold applications, cold whirlpool, or electrical stimulation.

EARLY HEALING PHASE
Range of Motion Exercises : As healing gets underway, it is important to begin a series of movement exercises for range of motion (ROM). At first, you'll work on bending and straightening the ankle. Later, diagonal motions can be used.

Strength Progression : Next, you'll begin a strengthening progression for the muscles around the ankle. Emphasis should be placed on the muscles that pull the foot up and out (evertors), up (dorsiflexors), and that raise the heel (plantarflexors). Isometrics may be chosen in the early stages of rehabilitation. These are strengthening exercises in which the muscles are working but the joint stays stationary. They allow you to exercise with the ankle at different angles, helping you stay away from painful positions of the ankle. These exercises provide the benefit of reducing overall pain and swelling. They also help the muscles remember what they're supposed to be doing.

Early resisted exercises : Some types of equipment are helpful in reducing the effects of gravity, allowing you to begin strengthening without causing pain. One example is the sled. It can be set at lower angles at first and then gradually progressed over the course of physical therapy as pain eases. Therapeutic band, pulleys, or isokinetic device may be used to apply progressive resistance to the muscles around the ankle.

Balance exercises : These exercises are especially important following a ligament injury. Healthy ligaments send information to the central nervous system about the position of a joint. That's partly why when we close our eyes we know precisely where our limbs are positioned. Once a ligament has been injured, these receptors are unable to receive and send the needed information to the brain. This increases the possibility of injury in the future. Balance exercises help restore this position sense by heightening the sensitivity in the remaining intact receptors. Examples of these types of exercises involve standing and walking on uneven or very soft surfaces, single leg balance, mini trampoline balance, and progressive agilities.

LINKS TO MORE INFORMATION

American Podiatric Medical Association - Foot and Ankle Injuries

American College of Foot And Ankle Surgeons - Ankle Sprains and Treatments

SOAR Medical Associates - Ankle Sprain & Instability

The Rothman Institute at Jefferson - Ankle

Stuart Zeman, MD - Ankle Sprain