Unrecognized injuries of the lateral ligaments associated with lateral malleolar fractures of the ankle.

Of four patients who were treated between May 1985 and November 1987 and who had both a lateral malleolar fracture and a tear of the lateral ligaments of the ipsilateral ankle, three could be followed. The fractured malleolus was treated with rigid internal fixation, but the injury to the lateral ligaments was not diagnosed until the ankle was stressed to test for stability after the internal fixation. We believe that if disruption of the lateral ligaments is noted at operation, repair is indicated. This involves only a slight prolongation of time under anesthesia and markedly increases the chances for a stable ankle. It is important to check intraoperatively for a possible tear of the lateral ligaments in a patient who has a fracture of the ankle, especially when the injury was caused by high-energy trauma.