The subtalar sprain. A roentgenographic study.

Subtalar and ankle sprains are more frequently associated than previously suspected. In this study, 40 patients were analyzed, using subtalar arthrograms and ankle stress films. Thirty-two of the 40 patients had a rupture involving components of both subtalar and ankle capsuloligamentous structures. If ignored or improperly treated, these lesions may develop into a sinus tarsi syndrome or a chronically painful and unstable ankle. Negative stress films in the presence of a clinically serious ankle injury should arouse suspicion of an underlying subtalar sprain, as demonstrated in six patients with positive arthrograms.