Maisonneuve fracture without deltoid ligament disruption: a rare pattern of injury.

The Maisonneuve fracture is considered by many to be one of the most unstable ankle injuries. We report a rare injury involving fracture of the proximal fibula in association with a posterior malleolar fracture and disruption of the anterior-inferior tibiofibular ligament, without disruption of the deltoid ligament or fracture of the medial malleolus. This report of a diagnostically challenging case highlights the importance of timely clinical and radiographic reassessment of a patient who fails to improve with initial therapy, and describes the clinical and diagnostic imaging findings of an unusual ankle injury.