Entrapped posteromedial structures in pilon fractures.

OBJECTIVES

To analyze a patient cohort who sustained a tibial pilon fracture and report the incidence of interposed posteromedial soft tissue structures.

DESIGN

Retrospective cohort review.

SETTING

Regional Level 1 Trauma Center.

PATIENTS/

PARTICIPANTS

About 394 patients with 420 pilon fractures treated between January 2005 and November 2011.

INTERVENTION: Each patient's preoperative radiographs and computed tomography (CT) images were reviewed. The axial and reconstructed images were used in bone and soft tissue windows to identify any posteromedial soft tissue structures incarcerated within the fracture.

MAIN OUTCOME MEASUREMENTS: Medical charts reviewed for the presence of preoperative neurologic deficit, separate posteromedial incision, and whether attending radiology CT interpretation noted the interposed structure.

RESULTS

40 patients with 40 fractures (9.5%) had an entrapped posteromedial structure. The tibialis posterior tendon was interposed in 38/40 fractures (95%) and the posterior tibial neurovascular bundle in 4/40 fractures (10%). Preoperative neurologic deficit occurred in 5/40 patients (12%). A posteromedial incision was used in 11/40 fractures (27%). The attending radiology CT interpretation noted the interposed structure in 8/40 fractures (20%).

CONCLUSIONS

In addition to the osseous injuries, CT imaging can demonstrate the posteromedial soft tissue structures. In our series, the tibialis posterior tendon was commonly incarcerated. In some cases, removal of the entrapped structure(s) may not be possible through the more commonly used anterolateral and anteromedial surgical approaches, and a separate posteromedial exposure may be required. Failure to recognize the presence of an interposed structure could lead to malreduction, impaired tendon function, neurovascular insult, and the need for further surgery.

LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.