The Posterolateral Approach to the Ankle: A Case Series with Technical Insights, Pitfalls, and Clinical Outcomes

Abstract

Retrospective Case Series. To evaluate the clinical and radiographic outcomes of posterior malleolar (PM) fractures treated through a posterolateral approach and to identify approach-specific technical pitfalls and anatomical considerations relevant to complication avoidance, particularly those related to the peroneal artery, intercalary fragments, and the flexor hallucis longus (FHL). 20 consecutive adult patients with ankle fractures involving the PM were treated through a posterolateral approach. Indications for surgical treatment via a posterolateral approach were based on CT-defined PM fracture patterns with displacement ≥ 2 mm, including Mason type 2a, 2b, or 3 and Bartoníček/Rammelt type 2–4 fractures. Surgical technique emphasized protection of the peroneal artery and FHL, anatomic reduction of all fragments, syndesmotic stabilization when indicated, and routine use of intraoperative 3D imaging. Clinical and radiographic outcomes, as well as complications, were assessed at standardized follow-up intervals up to 12 months. 17 patients completed follow-up. All PM fragments were fixed with a plate. The fibula was addressed through the same incision in 14 cases; additional posteromedial ( n  = 4) or medial ( n  = 5) approaches were used when required. Syndesmotic stabilization with a suture button was performed in 7 cases. Intraoperative 3D imaging confirmed anatomic reduction and correct incisural alignment in all patients. Complications included one transient sural nerve hypesthesia. No peroneal artery injury or FHL dysfunction occurred. All fractures united. Progressive full weight bearing was initiated at 3 weeks using a walker boot. At 12 months, mean range of motion was 9° dorsiflexion and 47° plantarflexion (contralateral 13°/58°). Mean Olerud-Molander Ankle Score (OMAS) and American Orthopaedic Foot & Ankle Society (AOFAS) scores were 78 and 88, respectively. FHL function was preserved in all cases. The posterolateral approach allows reliable reduction and fixation of appropriately selected PM fractures, resulting in favorable clinical and radiographic outcomes. This case series highlights practical strategies to avoid approach-specific complications. Particular attention should be paid to the peroneal artery, intercalary fragments, and the FHL, as complications involving these structures are likely underrecognized. Careful dissection, dual-compartment exposure, and anatomic reduction are key to minimizing vascular and tendon-related complications.