Insufficiency fracture of the talus: diagnosis with MR imaging.

PURPOSE: To describe the clinical setting and pattern of talar insufficiency stress fractures as diagnosed with magnetic resonance (MR) imaging. MATERIALS AND METHODS: The authors retrospectively reviewed the clinical history and MR images from four patients with five talar insufficiency fractures. All patients were women (age range, 30-70 years). Images were evaluated for the location and orientation of fractures and the presence of concomitant osseous and soft-tissue injury. RESULTS: Concomitant fractures were identified in two patients. Only two fractures were typical in location and orientation at the talar neck. Three fractures were atypical in location and orientation. One occurred horizontally in the talar body and two occurred in the posteromedial talus (one was oriented vertically and one horizontally). Two patients had associated concomitant stress fractures--one in the distal tibia and one in the calcaneus. CONCLUSION: The location and orientation of talar insufficiency fractures is more variable than previously recognized. Specific diagnoses and coexisting fractures can be determined with MR imaging.