Use of a 30-Degree External Rotation View for Posteromedial Tubercle Fractures of the Talus

Abstract

A fracture of the posteromedial talar tubercle is also referred to as the Cedell fracture and is an infrequently described injury. Failure to recognize this injury may lead to posteromedial ankle pain and tarsal tunnel syndrome. It is therefore important to diagnose these fractures at the time of the initial presentation to avoid future morbidity. Although plain radiography forms the mainstay of initial radiological evaluation of the ankle, these fractures are commonly missed and misdiagnosed because of poor visualization on routine ankle radiographs. Computed tomography helps for better visualization of this fracture at the higher risk of radiation. We evaluated the use of the 30-degree external rotation view for the diagnosis of fractures of the posteromedial tubercle of the talus using cadaver specimens. On the 30-degree external rotation view of the ankle, all fractures of the posteromedial tubercle of the talus were revealed. In contrast, the fracture was visualized in only 2 cases using the standard lateral radiograph of the ankle, and not once in the anteroposterior or mortise views. In conclusion, a 30-degree external rotation view is likely to show a fracture of the posteromedial tubercle of the talus in contrast to the 3 routine trauma views of the ankle, aiding in diagnosis and treatment strategy at time of initial presentation.