A Rare Coexistence: Avascular Necrosis of the Talus with Osteochondritis Dissecans – A Case Report

Avascular necrosis (AVN) of the talus and osteochondritis dissecans (OCD) are uncommon conditions affecting the ankle joint, each with distinct pathophysiologies and clinical implications. The talus’s unique vascular anatomy renders it susceptible to AVN, especially in the setting of trauma or compromised vascular supply. OCD, conversely, is typically linked to repetitive microtrauma leading to subchondral bone fragmentation and cartilage instability. Their simultaneous occurrence is exceedingly rare and presents diagnostic as well as therapeutic challenges. We report the case of a 46-year-old female who presented with progressive pain and tenderness over the ventral aspect of the ankle, aggravated by weight-bearing activities. Imaging with radiography, computed tomography (CT), and magnetic resonance imaging (MRI) revealed features consistent with avascular necrosis of the anterior talus and a displaced osteochondral fragment over the medial talar dome, suggestive of OCD (Stage IV – Berndt and Harty