A retrospective review of the clinical records and radiographs of 1344 ankle sprains occurring over a 41-month period at the United States Military Academy was performed. The incidence and severity of these sprains did not differ significantly from other studies with the exception of those injuries involving the tibiofibular ligaments. Those patients sustaining incomplete injuries to the ankle syndesmosis had a recovery time of almost twice that of those patients with severe (3rd degree) ankle sprains (55 vs. 28 days). Eight of 13 patients with 10 of 15 incomplete syndesmosis injuries were available for follow-up examination and radiographs at an average time of 20 months postinjury (range of 7-39 months). All patients with this injury had a positive "squeeze test" (compression of the fibula to the tibia at mid-calf) at the time of initial examination. Nine of 10 patients developed ossification of the syndesmosis in follow-up radiographs. None of these patients had developed chronic ankle instability, loss of motion, or arthritic changes of the joint at the time of final followup.