SLR - May 2013 - Kelly M. Pirozzi
Reference: Crim J, Enslow M, Smith J. CT Assessment of the Prevalence of Retinacular Injuries Associated with Hindfoot Fractures. Skeletal Radiol. 42:487-492, 2013. DOI: 10.1007/s00256-012-1530-2
Scientific Literature Review
Reviewed by: Kelly M. Pirozzi, DPM
Residency Program: Temple University Hospital; Philadelphia, PA
Podiatric Relevance: This study aims to determine the prevalence of injuries to the flexor and peroneal retinacula in hindfoot fractures by utilizing computed tomography (CT). The incidence of retinacular injuries in ankle fractures and their overall contribution to long-term fracture outcomes are unknown. Additionally, soft tissue injuries in the management of simple and complex hindfoot fractures are often underdiagnosed. By becoming more aware of these injuries in traumatic hindfoot pathology, we may be able to improve long-term outcomes in these patients.
Methods: This study was conducted at a single level-one trauma center over a two year period and 118 ankle fractures were reviewed. Patients for this study were identified by reviewing the radiology information system for all ankle CT examinations at this institution. All patients included in this study were over the age of 18. CT scans were retrospectively reviewed by a musculoskeletal radiologist and compared with their surgical reports. Fractures were divided into five categories: pilon, malleolar, distal tibial shaft with extension into ankle mortise, talus or calcaneus. A retinacula was considered torn when discontinuity was visible, or when it did not attach to the normal anatomic site. A tendon was considered torn or injured with low attenuation within its substance and also evaluated for displacement from normal position.
Results: Hindfoot fractures undergoing CT showed normal-appearing retinaculum in 51 patients. Indeterminate appearance was found in 27 patients and retinacular injuries were found in 40 patients. Flexor retinacular injuries were found in 23.7 percent of cases and peroneal retinacular injuries in 10.2 percent. Only 2 percent of patients had both flexor and peroneal retinacular injuries. The posterior tibial tendon was partially torn in 4.2 percent of cases, and entrapped in 16.1 percent of cases. In 9.3 percent of cases, the posterior tibial tendon was subluxed or dislocated, and all of these cases were found to have associated retinacular injuries. The peroneal tendons were found to be subluxed or dislocated in 5.1 percent of cases, all of which were found to have retinacular injuries. Intraoperative evalution of flexor retinaculum injuries resulted in four true-positives and 12 true-negatives. The posterior tibial tendon was evaluated in 16 cases and was found to have six true-positives, nine true-negatives, and one false-negative. Peroneal retinaculum injuries were evaluated in seven cases. There was one true-positive and there were six true-negatives. Peroneal tendons were found to have all true-negatives out of seven cases.
Conclusions: This study showed that the flexor retinaculum was more commonly injured than the peroneal retinaculum in retrospective CT examination of hindfoot fractures at a single trauma center. The only hindfoot fracture that had a greater correlation to peroneal retinacular injuries was calcaneal fracture. The study also found retinacular injuries to be more common in tendon subluxation or dislocation injuries with an associated fracture. Limitations to this study included bias and limited outcome data. Injuries that undergo CT evaluation are more severe fractures and therefore these results cannot be generalized for all hindfoot fractures. Outcomes could also not be assessed secondary to limited follow-up at this institution.