Ankle sprain
Ankle sprain is a clinical diagnosis from an inversion injury with lateral ligament tenderness, graded by severity, and the Ottawa ankle rules determine which patients need radiographs to exclude fracture before starting conservative treatment.
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What this article covers
- Overview
An ankle sprain is a ligamentous injury of the ankle, most often the lateral ligament complex, caused by an inversion mechanism that stresses the anterior talofibular ligament (ATFL) and, with…
- Epidemiology
Most common mechanism is inversion injury: excessive ankle inversion, often from stepping off a curb, landing awkwardly, or "rolling" the ankle during sport, accounts for the large majority of ankle sprains.
- Risk factors
Ligamentous laxity: connective tissue disorders such as Ehlers-Danlos syndrome predispose to sprain with lower-energy mechanisms.
- Pathophysiology
Plantar flexion and inversion injures the ATFL first: the ATFL is the weakest and most anterior of the lateral ligaments and is under the greatest tension in this position, making it the most frequently torn ligament in a low ankle sprain.
- Clinical features
Acute inversion mechanism (rolling the ankle, stepping off a curb or uneven surface) with immediate lateral ankle pain: the hallmark history.
- Differential diagnosis
Ankle fracture: typically follows a higher-impact mechanism; unlike a sprain, weight bearing is characteristically impaired, and bony tenderness at the posterior edge or tip of the malleolus meets…
- Diagnosis
Ankle sprain is a clinical diagnosis established by an inversion mechanism with lateral ligamentous tenderness (ATFL, and CFL with greater force) and a positive anterior drawer or talar tilt test…
- Management
First, apply rest, ice, compression, and elevation (RICE), and fit a lace-up ankle support or air stirrup brace with elastic compression wrapping for symptomatic relief and mechanical support during early healing.
- Complications
Chronic ankle instability: ongoing pain or instability persisting more than 6 months after injury occurs in a minority of patients and reflects residual laxity and impaired proprioception.
- Prognosis
Most grade 1 and grade 2 lateral ankle sprains recover fully within 2 to 6 weeks with RICE, bracing, and early functional rehabilitation.
- Prevention
Proprioceptive and balance training (for example single-leg balance board exercises) for athletes with a prior ankle sprain, continued for at least 4 to 6 weeks after the acute injury and maintained…
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