Marginal fractures of the lateral malleolus in association with other fractures in the ankle region.

Eight cases of avulsion-type fracture of the distal fibula associated with fracture of the calcaneus, talus, or ankle region were identified. This avulsion fracture can be identified on routine radiographs as well as on CT scans of the ankle and is pathognomonic of rupture of the superior peroneal retinaculum with or without peroneal tendon displacement. Recognition of this avulsion fracture, with subsequent proper management of the underlying peroneal tendon pathology by immobilization or surgery, may prevent future tendon dysfunction. It may also alter the treatment of other associated injuries.