Reduction quality in posterior malleolar fractures with anterior tibiofibular syndesmosis injury using the posterior to anterior malleolar extended lateral approach (PAMELA) with dual-window technique: a multicenter retrospective case series

Based on multicenter clinical data, the study aimed to assess the reduction quality and short-term exploratory functional outcomes of the posterior to anterior malleolar extended lateral approach (PAMELA) with the dual-window technique in the treatment of low-energy rotational ankle fractures involving posterior Malleolar fractures with anterior tibiofibular syndesmosis injury. A total of 89 patients were included. The PAMELA was performed on all patients, with two surgical windows (anterior tibiofibular syndesmosis window and posterolateral window) established through a single incision. The primary outcomes were radiographic reduction quality. Overall ankle fracture reduction was assessed using Burwell-Charnley radiographic criteria on postoperative X-rays. Posterior malleolar articular surface reduction and tibiofibular syndesmosis reduction were assessed using CT scans. At the final follow-up, exploratory functional outcomes were evaluated using the AOFAS ankle-hindfoot score, VAS, and ROM. All 89 patients completed follow-up. The follow-up duration was 14.0 months (range, 13.0–16.0 months). All fractures achieved union, and the time to union was 13.0 weeks (range, 12.0–14.0 weeks). Postoperative X-rays showed that all patients (100%) achieved anatomical reduction of ankle fractures. Postoperative CT scans revealed that 87 (97.8%) patients achieved excellent posterior malleolar articular surface reduction (≤ 1-mm step-off in the sagittal plane), 2 (2.2%) patients had satisfactory reduction (1-2-mm step-off), and none had poor reduction (≥ 2-mm step-off). Syndesmotic malreduction occurred in 1 (1.1%) patient. At the final follow-up, the AOFAS ankle-hindfoot score of patients was 91.0 points (range, 88.0–98.0), with 63 (70.8%) patients rated as excellent, and 26 (29.2%) patients as good. The VAS pain score was 0.0 (range, 0.0–1.0). The ROM of ankle plantar flexion and dorsiflexion was 30.0° (range, 25.0°-35.0°) and 10° (range, 5.0°-15.0°), respectively. This multicenter retrospective case series (Level IV evidence) suggests that for strictly selected low-energy rotational ankle fractures with posterior malleolar fractures with anterior tibiofibular syndesmosis injury, the PAMELA dual-window technique can achieve favorable CT reduction results and acceptable short-term exploratory functional outcomes. Due to the lack of a control group, this study cannot confirm that this technique is superior to traditional surgical approaches; it can only be considered an alternative surgical option for such injuries.