Perioperative Implant-associated Fractures in Geriatric Pertrochanteric Fixation: Incidence, Risk Factors, and the Influence of Proximal Femoral Geometry

Background: Perioperative implant-associated fractures (PIAFs) are defined as new cortical or structural disruptions occurring during nail insertion and represent an under-recognized complication associated with cephalomedullary nailing in geriatric pertrochanteric fractures. Objectives: This study aimed to evaluate the incidence, associated factors, and radiographic characteristics of PIAFs in a consecutive cohort. Materials and Methods: A retrospective review was conducted on 258 patients aged ≥60 years who underwent fixation with either proximal femoral nail antirotation II™ or INTERTAN™ devices between 2019 and 2022. Demographic variables, proximal femoral morphology, reduction quality, fixation parameters, and early postoperative radiographs were analyzed. Results: PIAFs occurred in 17 patients (6.6%). In univariate analysis, patients with PIAFs had higher body mass index ( P = 0.04), smaller low–lesser trochanter width (LLTW) ( P = 0.046), and more frequent use of the INTERTAN™ device ( P = 0.005). Multivariate regression identified reduced LLTW (odds ratio [OR] = 0.73) and INTERTAN™ implantation (OR = 12.66) as independent predictors. Traditional radiographic parameters – including reduction quality, medial cortical support, tip–apex distance, and the Cleveland index – were not associated with PIAFs. Sixteen PIAFs were nondisplaced and healed with protected weight-bearing, while one distal cortical fracture required revision to a long nail. Conclusions: PIAFs occurred in approximately 1 in 15 geriatric pertrochanteric fracture fixations. Narrow LLTW and INTERTAN™ use were independent risk factors. Careful attention to proximal femoral morphology and implant selection may help reduce PIAF risk.