Ankle Sprain

Causes

An ankle sprain occurs following a twisting movement the foot. Walking on slippery or uneven ground, wearing high heels or shoes that are worn or unsuitable for the activity in question, as well as sports activities can increase the risk of spraining an ankle. A sprain can sometimes be sustained as a result of problems with coordinating movements or loss of “righting reflexes” (disease, fatigue, alcohol, age).

What is an ankle sprain ?

An ankle sprain is when the ligaments are injured.

Ligaments are bands of fibrous tissue, composed mainly of collagen, that are very resistant and extendable. Their role is to join the bones together and to maintain contact between the joint surfaces during movement. They confer the joint mobility as well as stability by restricting certain movements.

A strain occurs when the joint is twisted too far. In 90% of cases, the lateral external ligaments are affected following a violent movement of the foot inwards. With the mildest forms, the ligaments are stretched, but with more serious sprains, the ligaments can be partially or completely torn.

Symptoms

The main symptoms of an ankle sprain are pain, edema (swelling), difficulty in moving the joint, ecchymosis (bruising), the intensity of which vary according to the severity of the lesion.

Minor sprain

The ligaments are only stretched slightly causing moderate pain and minor swelling. Mobility is not reduced.

Moderate sprain

The ligaments are stretched and partially torn. The pain is more intense. Swelling and bruising appear due to the bleeding caused by the tear. Mobility is deteriorated and the ankle can twist abnormally. It is painful and even impossible to put any weight on the foot.

Severe sprain

With a severe sprain, one or several ligament bundles are completely torn resulting in temporary, almost complete loss in mobility. The pain is immediate and very sharp, and the swelling and bruising are more significant. In addition, the sprain can be compounded by a luxation (dislocation of the joint), tendon rupture or an avulsion fracture.

Treatment

The diagnosis should be verified before defining the treatment. The immediate error is to confuse an ankle sprain with a fracture. Minor sprains do not require any emergency treatment. However, it is recommended to rapidly seek medical advice when there is significant bruising or swelling and have an x-ray to enable a differential diagnosis. Other examinations such as a scan may be carried out to narrow down the clinical diagnosis and help determine the most appropriate treatment.

An ankle sprain can take 3 to 6 weeks to heal according to the severity.

Convalescence can last up to 6 months in the case of a severe sprain requiring surgery.

RICE (Rest, Ice, Compression and Elevation)

Rest: this involves relieving the joint while the ligaments heal. However, complete rest is not recommended for more than 48 to 75 hours as the progressive stimulation of the joint promotes healing. Putting weight on the injured foot is not always proscribed; it is recommended to put weight on the member progressively according to the degree of pain. Crutches can be used to get around to start with so as not to put too much weight on the ankle.

Ice : ice (ice bag or bag full of ice cubes) can be put on the injured part of the ankle regularly, 4 times a day on average, over the first few days for as long as the joint is swollen and painful. The ice helps reduce the pain, edema and inflammation. If applied soon enough after the injury, it can also limit bleeding caused by the tear. However, it is strongly recommended not to apply heat as this could worsen the bleeding or damage the ligaments further.

Compression : this is generally achieved with strapping or an inflatable splint available on prescription. Compression helps reduce the edema and ecchymosis, and allows the affected ligaments to rest. The compression must not be too tight so as not to impair blood circulation.

Elevation : it is recommended to raise the injured member as often as possible to improve venous return and decrease the quantity of liquid in the damaged area due to the inflammation.

Medicinal treatment

Analgesics and anti-inflammatories are generally recommended. They provide relief, but are not strictly speaking involved in healing: they do not promote healing of the ligaments.

Immobilization

In general, the joint is only partially mobilized to prevent putting the damaged ligaments under strain so they can heal. The ligaments in the ankle are lateral, so twisting or rotational movements should be avoided. On the contrary, flexion/extension movements along the axis of the ligaments (as with walking) are generally not contra-indicated. The ankle is often immobilized using a splint, strapping or a brace. However, a plaster cast, which completely immobilizes the ankle and increases the risk of phlebitis and muscle wasting, is rarely indicated. It is restricted to serious sprains where the ligaments are seriously affected requiring greater immobilization or following an operation.

Surgery : ligament reconstruction

This consists in reconstructing the damaged ligaments using a graft taken from another part of the body or a synthetic material. The procedure is generally carried out under regional anesthetic.

Scheduled ligament reconstruction

We talk of a scheduled procedure when treating chronic lesions or ankle instability. The aim is to restore stability in order to prevent the natural progression leading to cartilage wear and deterioration of ankle function. As with any operation, there is a risk of infection and thromboembolism, but nowadays these complications are well managed and the results are very encouraging: in 90% of cases, the patient recovers a stable ankle with improved joint function.

Emergency ligament reconstruction

This is performed following trauma injuries and is indicated in the case of a strain with partial or complete ligament rupture, especially in young subjects or athletes. The aim is to restore ankle function as well as optimal, lasting joint stability.

Convalescence following this treatment is longer. The ankle is kept in a plaster cast (resin) for 6 weeks. During this period it is contra-indicated to put any weight on the foot. Once the cast has been removed, the patient can start putting weight on the foot and rehabilitation can begin. The patient should be able to walk normally within about 2 months of the operation and routine activities can be resumed within 3 to 4 months. It is however necessary to wait 6 months before resuming any intensive sports.

Rehabilitation

Rehabilitation can begin at a physiotherapy clinic and continue at home with the exercises learned for as long as the ankle is weak. The aim is to stabilize the joint to avoid any relapses, but also to fight the onset of chronic instability that could ultimately damage the joint cartilage leading to pain and osteoarthritis.

Rehabilitation consists in stimulating the ligaments to restore their elasticity and tonicity, and strengthening the muscles, often atrophied after a period of inactivity, in order to consolidate the joint.

Some techniques also help improve “righting reflexes” that can be the cause of primary or recurrent sprains.