CT assessment of the prevalence of retinacular injuries associated with hindfoot fractures.

Abstract

To determine the incidence of injuries to the flexor and peroneal retinacula in hindfoot fractures as demonstrated on ankle computed tomography (CT). Study patients were identified via review of CT records at a single institution. CT scans were retrospectively reviewed and compared with surgical reports. Hindfoot fractures undergoing CT showed flexor retinacular injuries in 23.7% of cases and peroneal retinacular injuries in 10.2%. The posterior tibial tendon was partly torn in 4.2% of cases, and entrapped between fracture fragments in 16.1%. The peroneal tendon was rarely injured, being entrapped in 1.7% of cases. Pilon, distal tibial shaft, malleolar, talar, and calcaneal fractures were all associated with retinacular injuries. CT findings correlated well with surgical findings; there were no false-positive CT findings, and only 1 false-negative finding, a posterior tibial tendon that was entrapped at surgery, but in a normal position on the CT. Retinacular injuries are commonly demonstrated on CT in patients with ankle fractures. The contribution of these injuries to fracture outcomes is unknown.