Lateral Ankle Ligament Sprains Inversion Ankle Sprains

Lateral Ankle Ligament Sprain

Lateral ankle sprain refers to an injury to the ligaments located on the outer side of the ankle joint, leading to pain and swelling in the area.

Ligaments are tough bands of fibres that extend from one bone to another. Ligaments serve to hold the bones together in a joint, allowing them to move within a specific range without getting displaced. Any abnormal movement or stress at the joint may cause over-stretching or even tearing of the ligaments, referred to as a sprain.

Ankle sprains are the most common orthopedic injuries, and most of these result from injury to the lateral ankle ligaments. Lateral ankle sprain is quite common among sportspersons and accounts for about 10 -15% of all sports-related injures. Volleyball, basketball and soccer players are most at risk of acquiring a lateral ankle sprain. However, a person can twist his ankle even while walking normally during routine activities.

The ankle joint is formed between the bones of the lower leg tibia and fibula and those of the hind foot, mainly the anklebone (talus).

A number of ligaments hold these bones in the ankle joint. These ligaments are divided into two main groups. The ligaments located on the outside of the ankle are called lateral ligaments. The ligaments located on the inner side of the ankle are called medial ligaments (deltoid ligaments).

There are three major ligaments located on the outer side of the ankle, which join the fibula (the bone on the outer side of the leg) to the anklebone (talus) and heel bone (calcaneus).

These are:

the anterior talo-fibular ligament (joining the fibula to the talus, located in the front)

the calcaneo-fibular ligament (joining the fibula to the calcaneus, located in the middle)

the posterior talo-fibular ligament (joining the fibula to the talus, located at the back)

In a lateral ankle sprain, the ligament located in the front, i.e. the anterior talo-fibular ligament, takes most of the impact, and therefore it is the one most commonly injured.

The ligament in the middle, the calcaneo-fibular ligament, is a strong ligament, but in severe cases, it may also be involved. The posterior talo-fibular ligament, which is located further back, is involved only rarely.

Cause:

Lateral ankle sprain occurs due to accidental inward rolling (inversion) of the foot. This can happen while walking on an irregular surface, jumping and running (as in sports), walking in ill-fitting or high-heeled shoes, etc. When the foot twists inwards, the ligaments on the outer side of the foot are stretched beyond the normal range and are torn. The ligaments may also be damaged due to a direct impact. The extent of damage depends upon the extent to which the foot is twisted, and can be categorized into:

Grade I sprain: minimum damage, the ligament is overstretched, little pain and swelling, minimal or no functional impairment

Grade II sprain: moderate damage, the ligament is partially torn, moderate pain and swelling, impairment of function, difficult to walk or put pressure on the affected joint

Grade III sprain: severe damage, the ligament ruptures completely, resulting in joint instability, severe pain and swelling, making it impossible to stand or walk on the affected side

Persons who have previously suffered from an ankle sprain are twice as likely to acquire another sprain. Moreover, people born with weak ankles, obese persons or those involved in vigorous sports also have an increased risk of suffering from a lateral ankle sprain.

Symptoms:

• Pain on the outer front or side of the ankle
• Pain intensifies with movement
• Swelling and bruising
• Tenderness of the area
• Difficult to place weight or walk on the affected side
• Stiffness of the joint

The intensity of symptoms depends upon the type of injury; with type I showing minimal symptoms while type III causes severe pain and disability.

When there is a history of previous ankle sprain, the person may not feel much pain or swelling, just a little instability during walking. Therefore, to be on the safe side, if such an injury occurs it is better to get it examined properly.

Diagnosis:

The mechanism of injury, the signs and symptoms as well as a careful clinical examination help in diagnosing the condition. An X-ray may be advised to rule out any associated bone fractures.

Treatment:

Treatment depends upon the extent of the injury and the overall condition (associated bone fracture, tendon injuries, etc.)

Conservative treatment usually gives good results in most of the cases. It includes:

Rest: no movement or pressure on the joint

Ice application: for about 15-20 minutes several times a day in the first 48 hours

Compression: compressing the joint with the help of an elastic bandage (take care not to apply it too tightly to affect the normal blood flow)

Elevation: of the injured joint above the heart level to improve drainage.

Following this RICE protocol in the initial period helps to control pain and swelling and decreases inflammation.

Non-steroidal anti-inflammatory painkillers also reduce pain and swelling. These are available in the form of tablets or as creams or gels which can be rubbed over the affected area.

Immobilization of the foot using a semi-rigid or rigid cast helps to protect and support the joint and gives the ligaments time to heal properly. The cast or splint may be applied for four to six weeks depending upon the severity of the injury.

Crutches may also be needed for a short time.

Surgical intervention for the treatment of lateral ankle sprains is rarely required and is only indicated when the ligaments are severely damaged, resulting in joint instability, or in case of recurrent ankle sprains due to incomplete healing or loosening of the ligaments.

Surgery involves:

Tightening the ligaments and reattaching them to the bone

Replacing severely damaged ligaments using nearby tendons (fibrous bands attaching muscles to bones)

However, the advisability of surgical treatment of a lateral ankle sprain is debatable and in about 10-15% of cases, symptoms may persist even after surgery. Many consider immobilization of the foot using a rigid/semi rigid cast a better alternative for treating an unstable ankle.

Rehabilitation:

When the symptoms subside, it is better to start moving the joint gradually. Start with simple exercises such as bending the foot upward and downward. When these movements are possible without pain, try to rotate the foot in small circles or to draw letters with the toes.

These simple movements prevent excessive scar formation and help in proper healing of the ligament.

Exercises to strengthen the muscles around the ankle improve joint stability and decrease the recurrence of ankle sprain.