Sprained Ankle

Sprained ankle, we’ve all had one at some point or other. This month’s bulletin tells us the causes, how to diagnose it and what to do if you’re unlucky enough to get one.

Welcome back to the Sports Injury Bulletin. This article will continue with disorders of the foot and ankle – specifically – the sprained ankle.

Most runners have experienced the sharp warning stab of pain following the sudden rolling of the ankle.

It usually occurs after clocking up many miles in a week, or towards the end of a long run when fatigue begins to creep in. This is more so with unaccustomed running on uneven terrain, or experiencing the hustle-and-bustle at the start of a packed organised run.

Whatever the circumstance, the mechanism is often the same, while the degree of damage can range from a mild ‘sprain’ to a complete tear of some of the key supporting structures of the ankle.

This article will explore the lateral ligament sprain of the ankle and offer advice on its management. As always, emphasis will be placed on preventative exercises.

The Ankle

The lateral collateral ligament of the ankle is the main supporting structure on the outside of the ankle and is the combined effort of three distinct bands of connective tissue (ligaments). The key player of which is the Anterior talofibular ligament – or ATFL to you and me!

These three ligaments work as a ‘complex’ to prevent excessive turning-in of the foot (inversion). This ligament complex also plays a key role in providing your nervous system with the feedback needed to maintain the joint in a stable position. This fact suggests that training this function of the ligaments could reduce the risk of rolling on the ankle.

The ankle and the lateral (outer) ligament complex:

Structure of the ankle

Sprain of the lateral ligaments of the ankle is the most common type of ankle injury, accounting for approximately 85-90% of all ankle sprains. The usual mechanism of injury is a forced inversion injury as depicted below:

Forced inversion ankle injury

It is estimated that 55% of people experiencing this type of injury do not seek treatment, and so a history of previous ankle sprain becomes a major predisposing factor for recurring ankle sprains.

Diagnosis

Diagnosis is often based on the reported mechanism of injury, pain on the outer aspect of the ankle with inversion of the foot, swelling, and sometimes severe bruising and discolouration. An X-ray is often unnecessary, although in rare cases bony damage can occur.

The severity of the sprain (tearing or plastic stretching of ligament fibres) is often indicated after several days when a doctor or physiotherapist is able to assess range of movement and stability. This leads to a classification of the severity:

Grade 1: Mild stretching of the ligament or surrounding structures with mild swelling and tenderness over the outer ankle. There may be some limitation of movement but no instability.

Grade 2: A partial rupture, usually of the ATFL. There is moderate to severe pain and swelling, bruising is common with a limited range of movement. Pain and difficulty weight bearing will be more than likely and the physiotherapist will detect some degree of instability on stressing the ankle.

Grade 3: Complete rupture, usually of two of the three ligaments. There is a large degree of instability of the ankle, although this may be difficult to detect in the first instance due to severe pain, protective muscle spasm, and a large amount of swelling.

Sounds like my ankle, what should I do?

Grade 1 sprain: Apply ice for the first 24-72 hours, using a damp cloth to protect the skin and check the area for ice burns frequently. A 20 minute application every 2 hours in recommended.

A compressive support is beneficial when up –and-about, but otherwise elevate the ankle where possible. With early gentle mobilisation including ankle movement exercises and steady weight bearing, the injury should resolve in 7-10 days.

Grade 2 sprain: This grade of injury can vary greatly but most recover in 14-21 days. Use the above strategies to limit the damage in the first 72 hours, before commencing gentle range of-motion exercises such as ankle-circles, and toe point-and-flex.

Progress to early mobilisation but limit the time spent on your feet and monitor the swelling to guide your effort. Gentle running should only commence when walking is pain-free and range-of-movement is full.

Grade 3 sprain: See above for managing the first 72 hours. Once the full extent of the damage is ascertained, surgery may be an option, but in most cases conservative management is the way forward.

Mobilise as the pain allows, unless in a plaster cast! Early mobilisation is the key, progressing to ROM exercises, resisted exercises against a fixed resistance, resisted exercise against a movable resistance, progressive weight bearing, and finally for all grades of injury – balance exercises.

These include wobble boards, walking on uneven ground, single leg balance, and single leg squats. Only when all of this is pain-free and easily achieved should running recommence.

Seek tailored advice from a suitably qualified physiotherapist or doctor for a suspected grade 2 or 3 tear to ensure a swift return to training.

Finally, these balance exercises (known as proprioception training) should be an ongoing part of your training to prevent ankle injuries or limit recurrent sprains. Go on, I challenge you make ankle injuries a thing of the past!

Until next time, run pain-free.

Ross Clifford MCSP is a practising Physiotherapist with a specialist interest in sport and exercise Physiotherapy. He also holds a Sport and Exercise Science degree and has taught in the area of Sports Injuries and the Biological Sciences. He is a keen runner and cyclist.