Split Fracture of the Posteromedial Tubercle of the Talus: Case Report and Proposed Classification System

We describe a rare case of a fracture of the medial tubercle of the posterior process of the talus in a 16-year-old male athlete who fell during basketball practice. The patient presented to our orthopedic clinic when pain and swelling had persisted despite 2 weeks of anti-inflammatory medication and rest. Computed tomography and magnetic resonance imaging scans revealed a fracture of the posteromedial tubercle of the talus and a small amount of retained fluid in the joint. Immobilization with a below-the-knee cast and non-weightbearing for 4 weeks, with a gradual return to full activity, was successful. At the 1-year follow-up evaluation, the patient expressed no complaints. Fracture of the posteromedial tubercle of the talus will usually result in a misdiagnosis or delayed diagnosis owing to the insidious onset of symptoms. We believe the present fracture configuration resulted from the vertical compression force that occurred on landing by posterior medial ankle impingement in plantarflexion-supination, modifying the conventional concept of the posteromedial tubercle fracture. We also present a suggested classification with a flowchart diagram.