Lateral ankle sprains are the most common lower limb musculoskeletal injury experienced by those who participate in sport. They also have a high prevalence in the general population as well. It is estimated that up to 70% of the population will experience a lateral ankle sprain in their lifetime. They also have the highest re-injury rate of all lower leg injuries. The likelihood of re-injury of the lateral ankle within in the next 12 months is doubled. It is believed that the high re-injury rates might be due to insufficient rehabilitation and/or premature return to sports.
Around 50% of people who have a lateral ankle sprain don't seek medical attention. Over time, an untreated ankle sprain can lead to chronic ankle instability. Symptoms of chronic ankle instability will often include ongoing pain, swelling or giving way with an extremely high likelihood of re-injury. For an athlete or sportsperson, this can lead to missing events or games while for the average person, it can affect your ability to work.
What causes a lateral ankle sprain?
A lateral ankle sprain occurs when the ankle rolls inward and the ligaments on the outside of the ankle stretch beyond their limits leading to tearing of the ligament fibres.
The most common cause of lateral ankle sprains come from landing on an uneven surface and losing balance with the ankle rolling inward. Some sports related causes include cutting or twisting through the foot or someone stepping on your foot while running.
At the moment of injury, the ankle will roll outwards while the foot rolls inwards leading to overstretching of the lateral ligaments of the ankle.
signs and symptoms of a lateral ankle sprain
Pain and tenderness of the ankle.
Bruising around the lateral aspect of the foot.
Difficulty to weight bare.
In extreme cases of high level sprains, a popping noise can be heard.
How are ankle sprains graded and what is the expected recovery time?
Ligament injuries are graded depending on the level of ligament fibres that are torn. These grades range from I to III.
Grade I - mild ankle sprain. Most common ankle sprain involving low levels of torn ligament fibres. Normal recovery time is around 2-3 weeks.
Grade II - moderate sprain. Partial tearing of the ligament fibres. Increased laxity of the joint common with the direction of injury. Depending on the severity of the sprain, recovery time for a grade II sprain can be anywhere from 1 month to several months.
Grade III - high level sprain. High levels of ligaments fibres torn, possible full thickness rupture. High levels of swelling and tenderness. It is important to rule out a possible fracture with grade III ankle sprains. Recovery times for a grade III sprain can vary widely depending on the level of damage done to the ligaments and bones of the ankle and whether or not surgery is required. In some extreme cases, a moon-boot or cast may be required to immobilise the joint which can lead to further delays in recovery time. Recovery time can very from several months to a year (possibly longer).
Predisposing factors for a lateral ankle sprain.
Height and weight - someone who is taller and heavier is more likely to suffer an ankle sprain than their shorter, lighter counterparts.
Previous injury - if you have sprained the ligaments in your ankle previously, you are more likely to experience recurring ankle injuries.
Postural sway (balance) - the movement of the centre of gravity during upright postures and the ability to control this can have a bearing on the likelihood of suffering an ankle sprain.
Unlike knee injuries, gender does not play a role in the likelihood of injuring the ligaments of the ankle.
Treatment and rehabilitation of a lateral ankle sprain (Grade I or low level Grade II)
Initial Stage (Inflammatory stage - first 3 days)
Rest - avoid weight baring on the injured foot for the first few days. Crutches might be required for the first 2 to 3 days while swelling is still high. Try to avoid being standing for long periods of time, elevate your foot where possible. Functional taping and supports (ie. brace) is preferred over complete immobilisation, but in some extreme cases immobilisation in the early stages may be beneficial in decreasing pain and swelling.
Ice or NSAIDs - while inflammation is an important part of the healing process, too much can be painful. Ice and non-steroidal anti-inflammatory drugs can be helpful in limiting inflammation and reducing pain in the early stages of injury.
Active/Passive Mobilisation - movement of the toes and ankle through pain-free ranges during the early stages of injury can help encourage circulation to the area and maintain ongoing joint ranges.
Recovery Stage (Proliferation phase - days 4 through 10)
Gradually increase activity levels - using symptoms as a guide, gradual return to activity is recommended as soon as possible. Start small with gentle ankle movements trough range of motion as pain and swelling allows. Ankle exercises within the first week drastically improve function of the ankle in the short term.
Taping/Bracing - an ankle brace or tape is to be applied to the ankle as soon as swelling starts to decrease. Patient preference as to whether to use tape or a brace.
Rehabilitation Stage (Remodelling phase - 10 to 21 days and onward)
Foot and ankle exercises - strengthen the muscles of the lower leg will help stablilise the ankle while the ligament continues to heal.
Stability and proprioceptive exercises - as load-bearing improves, start to focus on single leg balance, dynamic movement and motor control activities.
Continue taping/bracing during physical activity - decrease the risk of re-injury during the early stages of recovery.
For a full rehabilitation program, book a session with one of our practitioners.
Chronic Ankle Instability
Inability to seek medical advice for an ankle sprain can have ongoing effects. A high percentage of people who don't seek medical advice following an ankle sprain can develop chronic ankle instability.
Some symptoms include:
Delayed reflexes of the ankle stabilising muscles
Decreased lower leg muscle strength
Decreased proprioception and neuromuscular control
Impaired postural control
A structured program addressing the mechanical and functional insufficiencies of the ankle is recommended.
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Bleakley CM et al., Effect of accelerated rehabilitation on function after ankle sprain: randomised controlled trial., BMJ, 2010.
Delahunt E, Bleakley CM, Bossard DS, et al Clinical assessment of acute lateral ankle sprain injuries (ROAST): 2019 consensus statement and recommendations of the International Ankle Consortium
British Journal of Sports Medicine 2018;52:1304-1310
Vuurberg G, Hoorntje A, Wink LM et al. Diagnosis, treatment and prevention of ankle sprains: update of an evidence-based clinical guideline. Br J Sports Med 2018; 52(15): 956.