True Antiglide Fixation of Weber B Ankle Fractures has Lower Rates of Removal of Hardware

CATEGORY: Trauma; Ankle INTRODUCTION/PURPOSE: Plating of unstable OTA/AO 44-B1 lateral malleolus fractures has been associated with pain, peroneal irritation, and subsequent hardware removal. There has been speculation that this is due to the prominent plate and distal screw placement. Previous studies have looked at posterior vs lateral plate position but have had fairly low numbers in each group. The purpose of this study was to retrospectively compare the rates of hardware removal in unstable OTA/AO-type 44-B1 lateral malleolus fractures fixed with a posterior, true anti-glide plate with no screws in the distal segment versus those that were fixed with a similarly placed posterior, neutralization construct that included screws in the distal fragment thus evaluating the role of the distal screw in rates of hardware removal. METHODS: Skeletally mature patients that were treated for an isolated OTA/AO 44-B1 fracture over a ten-year period (2007- 2017) were reviewed. Fractures treated with a single posterior plate were included and those fixed with a direct lateral plate were excluded. We evaluated post-op radiographs to determine application of a true anti-glide plate or a neutralization plate with screws in the distal fragment. Radiographic follow-up was used to determine bony union, malunion and need for hardware removal. Hardware removal was determined as entire plate removal; isolated syndesmotic screw removal was not included. Patients were excluded if they had less than six months of follow up. Relative risk was determined for the rate of hardware removal based on fixation technique. RESULTS: There were 548 OTA/AO 44-B1 fractures treated over the course of ten years (2007-2017). After screening, 88 patients were included in the study. The majority of excluded patients lacked adequate follow-up. Average age of the cohort was 46 years old (range 17-84), with 47 females and 41 males included. Average length of follow up was forty months (range 6.1- 140.3). There were 28 patients in the true anti-glide plate group and sixty in the neutralization plate group. Five (18%) in the anti- glide plate group and 19 (32%) in the neutralization plate underwent a second procedure of hardware removal. Relative risk of hardware removal was 0.56 (95% CI 0.23-1.36, p=0.2). There was a 100% union rate with 0% malunion in both groups. CONCLUSION: Anti-glide plating has a near 50% relative risk reduction in the rate of hardware removal when compared to posterior based neutralization plating. Fractures fixed with or without distal screws had equivalent excellent results related to bony union and alignment. A true anti-glide plating construct should be considered as a safe and effective way of managing OTA/AO 44-B1 lateral malleolus fractures with a lower relative risk of a second operation for hardware removal.