Answer to ‘A 28-year-old snowboarder presents with chronic ankle pain’

In 24% of cases there is no history of acute trauma and the most common location for ankle osteochondral lesions is the medial-central talar dome. 1-3 Osteochondral lesions have been reported in 6.5% of acute ankle sprains and 38% of patients with persisting pain after an ankle sprain. 3 Osteochondral lesions may present with deep, non-specific ankle pain and tenderness to palpation in the anteromedial corner of the ankle joint with the foot in plantar flexion. Mechanical or functional instability and locking may or may not be present and the clinical findings often remain non-specific. 4 In the setting of chronic ankle pain, particularly with the insensitivity of plain radiography for subtle changes, 5 MRI has both a high sensitivity and specificity for osteochondral lesions and can assist with prognosis and treatment. 1 2 6 At a microscopic level, the term 'osteochondral lesion' encompasses pathology that can affect cartilage, the subchondral bone plate and cancellous bone of the talar dome.