Presentation
Left ankle pain and swelling following involvement in a road traffic accident
Patient Data




There is a medial malleolar fracture with a subtle lateral talar shift widening the medial gutter. A comminuted lateral malleolar fracture also noted at the level of the tibiofibular syndesmosis consistent with Weber type B fracture. An additional fracture line passing in the coronal plane to the articular surface of the posterior tibial plafond consistent with a posterior malleolar fracture. Soft tissue swelling noted
Features are those of left ankle trimalleolar fracture
Case Discussion
Trimalleolar fracture is a three-part fracture of the ankle involving the medial malleolus, lateral malleolus and posterior malleolus which is an intra-articular fracture of the posterior tibial plafond. It is, therefore, an unstable fracture commonly resulting in lateral displacement of the plafond over the talar trochlear, thereby resulting in ligamental and neurovascular injuries.
A close differential is the pilon fracture and can be differentiated from a trimalleolar fracture due to the presence of a profound comminuted distal tibial fracture, an intraarticular extension of the fracture line through the dome of the plafond, and the presence of a fractured talus.