Comparison between buttress plate and anteroposterior screw internal fixation for posterior pilon fracture: a retrospective study

Abstract Background Posterior pilon fracture (PPF) is a serious ankle injury caused by combined vertical and rotational trauma. Surgical treatment includes buttress plate (BP), anteroposterior screw (APS) and posteroanterior screw (PAS) fixation. This study aimed to compare the therapeutic effects after PPF internal fixation with BPs and APSs. Methods From January 2015 to June 2018, 37 patients with PPFs underwent surgical treatment in our institution. The patients were divided into the BP (11 patients) and APS (26 patients) groups according to the internal fixation method. Bone healing time and postoperative complications were recorded. At the last follow-up, American Orthopedic Foot and Ankle Society (AOFAS) scores, visual analog scale (VAS) scores and Burwell-Charnley scores were used to evaluate ankle joint function, ankle joint pain, and fracture reduction on imaging, respectively. Results No significant difference in bone healing time was found between the two groups ( P > 0.05). Local necrosis of the posterolateral incision and chronic ankle pain occurred in 1 case each in the BP group. Chronic ankle joint pain occurred in 4 cases in the APS group. Two cases of soft tissue irritation were caused by screws that were too long. Local numbness of the posterolateral incision occurred in 1 case. At the last follow-up, no significant difference in VAS scores between the two groups at rest ( P = 0.477), but a significant difference during exercise was noted ( P = 0.033). AOFAS scores were better in the BP group than those in the APS group ( P = 0.002). According to the Burwell-Charnley scoring system, 11 cases were anatomically reduced in the BP group. In the APS group, anatomical reduction was achieved in 19 cases and fair in 7 cases. Conclusion Compared with APSs, BPs resulted in better reduction, ankle joint functional recovery and complication rates. BPs are recommended for internal fixation of PPFs.