Intraoperative fluoroscopic evaluation of trochanteric fracture reduction using a novel anteromedial cortex view: A multicenter prospective observational study.

Abstract

Accurate intraoperative assessment of fracture reduction is essential in trochanteric fracture surgery to prevent mechanical failure. Although restoration of anteromedial cortical support, particularly in the sagittal plane, has been recognized as a critical factor, standard lateral views may fail to detect malreduction because the shadow of the greater trochanter overlaps and obscures the anteromedial cortical line. This study aimed to evaluate the clinical utility of a novel intraoperative anteromedial cortex (AMC) view for assessing fracture reduction. This prospective multicenter observational study included 135 trochanteric fractures (AO/OTA 31A1.2, 31A1.3, and 31A2) surgically treated between June 2022 and December 2023. In addition to standard AP and lateral fluoroscopic views, an AMC view was obtained intraoperatively. Reduction on the lateral and AMC views was categorized as anterior malreduction, anatomic reduction, or posterior malreduction. The primary outcome was the concordance rate between the lateral and AMC views. Discordances between lateral and AMC views were observed in 26 of 135 cases (19.3%). Notably, among fractures classified as anatomic reduction on the lateral view, 12 cases (19.4%) were reclassified as anterior malreduction on the AMC view, representing "hidden" anterior malreduction. In 7 of these 12 cases (5.2% of the total cohort), the AMC view findings directly led to a change in the surgical strategy, requiring direct reduction through a small incision. Approximately one-fifth of trochanteric fractures showed inconsistent reduction patterns between the standard lateral the AMC views. The AMC view provides a more precise intraoperative assessment of the anteromedial cortex and is particularly effective in identifying hidden anterior malreduction that may be overlooked on standard fluoroscopy.