Clinical Analysis of Posterolateral Approach for the Treatment of Posterior Malleolus Fracture with Cannulated Screw or Buttress Plate

Abstract Background:Posterior malleolus (PM) fractures account for 7%-44% of all ankle fractures. however, the management of PM fractures remains controversial. Studies have shown that the posterolateral approach is one of the most commonly used surgical approaches. The aim of this study was to evaluate the clinical effect of the posterolateral approach with cannulated screw or buttress plate for the treatment of posterior malleolus fracture.Method:We retrospectively analyzed the clinical data of 66 patients with ankle fractures involving posterior malleolus from January 2016 to March 2018. All patients were treated with a posterolateral approach. Fixation of the posterior malleolus was made with anterior to posterior (AP) lag screws in 7 patients, posterior to anterior (PA) lag screws in 38 patients, buttress plates in 9 patients, and buttress plates combined with PA lag screws in 12 patients. We used the AOFAS ankle and posterior foot function scoring system, VAS pain score, and radiographic evaluations as the primary outcome measures. The mean follow-up was 10.8 ± 4.4 (range, 6-20) months.Results:Radiological evaluation showed that 64 patients (97.0%) achieved a good or excellent reduction and the primary bone union was achieved in all the 66 patients without internal fixation failure or occurrence of post-traumatic ankle arthritis. At the final follow-up, the mean AOFAS score of the patients was 92.39 ± 3.84, with an excellent/good rate of 100%. The VAS pain score was 6.62±1.03 before surgery, changed to 3.06 ± 0.72 one week after surgery, and 1.20 ± 0.92 at the final follow-up. There was no statistical difference in the AOFAS score (p=0.01) or VAS pain score (p=0.01) between the different internal fixation methods.Conclusion:The posterolateral approach using lag screws and/or buttress plates can achieve good clinical outcomes in the treatment of posterior malleolus fracture with reduced incidence of postoperative complications, fracture reduction failure, and ankle osteoarthritis.