Atraumatic avascular necrosis of the head of the talus: a case report.

Avascular necrosis of the talus has frequently been reported following trauma. The incidence of avascular necrosis has been reported to be as high as 50% for Hawkins Type II talar fractures and to range from 75-100% for Type III fracture-dislocations. The resultant avascular necrosis has been reported to occur primarily in the body and dome of the talus with apparent sparing of the head of the talus. The close association of trauma to avascular necrosis of the talus has been alluded to by Cobey and others. Reports of avascular necrosis of the talus, without an antecedent history of trauma, have been rare. This paper presents a case of atraumatic avascular necrosis of the talar head.