Abstract
BackgroundAnteromedial cortical support apposition (positive and/or neutral cortical relations) is crucial for surgical stability reconstruction in the treatment of trochanteric femur fractures. However, the loss of fracture reduction is frequent in follow-ups after cephalomedullary nail fixation. This paper aimed to investigate the possible predictive risk factors for postoperative loss of anteromedial cortex buttress after nail fixation.MethodsA retrospective analysis of 122 patients with AO/OTA 31A1 and A2 trochanteric femur fractures treated with cephalomedullary nails between January 2017 and December 2019 was performed. The patients were classified into two groups according to the postoperative status of the anteromedial cortical apposition in 3D CT images: Group 1 with contact “yes” (positive or anatomic) and Group 2 with contact “No” (negative, loss of contact). The fracture reduction quality score, tip-apex distance (TAD), calcar-referenced TAD (Cal-TAD), Parker ratio, neck-shaft angle (NSA), and the filling ratio of the distal nail segment to medullary canal diameter in anteroposterior (AP) and lateral fluoroscopies (taken immediately after the operation) were examined in univariate and multivariate analyses. Mechanical complications were measured and compared in follow-up radiographs.ResultsAccording to the postoperative 3D CT, 84 individuals (69%) were categorized into Group 1, and 38 individuals (31%) were classified as Group 2. The multivariate logistic regression analysis showed that the poor fracture reduction quality score (P < 0.001) and decreasing filling ratio in the lateral view (P < 0.001) were significant risk factors for the loss of anteromedial cortical contact. The threshold value for the distal nail filling ratio in lateral fluoroscopy predicting fracture reduction re-displacement was found to be 53%, with 89.3% sensitivity and 78.9% specificity. The mechanical complication (varus and over lateral sliding) rate was higher in Group 2.ConclusionsThe fracture reduction quality score and the decreasing filling ratio of the distal nail to the medullary canal in the lateral view (a novel parameter causing pendulum-like movement of the nail) were possible risk factors for postoperative loss of anteromedial cortical support.
Highlights
Anteromedial cortical support apposition is crucial for surgi‐ cal stability reconstruction in the treatment of trochanteric femur fractures
The 1-point loss in most cases was due to the residual gap between the head–neck fragment and shaft, which was larger than one cortex thickness
Postoperative 3D CT full-range images revealed that 84 cases (69%) were categorized as having true anteromedial cortex contact, and 38 cases (31%) were categorized as having lost contact
Summary
Anteromedial cortical support apposition (positive and/or neutral cortical relations) is crucial for surgi‐ cal stability reconstruction in the treatment of trochanteric femur fractures. The loss of fracture reduction is frequent in follow-ups after cephalomedullary nail fixation. In 1980, Kaufer [7] proposed five factors that can predispose fixation complications and treatment failure: bone quality, fracture morphology, implant selection, implant placement, and, most importantly, fracture reduction quality. The apposition of anteromedial cortices between the head–neck and shaft was assessed by immediate postoperative fluoroscopy in both AP and lateral views. This factor was classified as exhibiting positive, neutral, and negative patterns [8]. Positive and neutral cortical appositions are acceptable; none of the negative relationships in the AP or lateral view was acceptable before nailing [9,10,11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
