Predictive factors of distal femoral fracture nonunion after lateral locked plating: a retrospective multicenter case-control study of 283 fractures.

Abstract Introduction Reported initial success rates after lateral locked plating (LLP) of distal femur fractures have led to more concerning outcomes with reported nonunion rates now ranging from 0 to 21%. Reported factors associated with nonunion include comorbidities such as obesity, age and diabetes. In this study, our goal was to identify patient comorbidities, injury and construct characteristics that are independent predictors of nonunion risk in LLP of distal femur fractures; and to develop a predictive algorithm of nonunion risk, irrespective of institutional criteria for clinical intervention variability. Patients and methods A retrospective review of 283 distal femoral fractures in 278 consecutive patients treated with LLP at three Level1 academic trauma centers. Nonunion was liberally defined as need for secondary procedure to manage poor healing based on unrestricted surgeon criteria. Patient demographics (age, gender), comorbidities (obesity, smoking, diabetes, chronic steroid use, dialysis), injury characteristics (AO type, periprosthetic fracture, open fracture, infection), and management factors (institution, reason for intervention, time to intervention, plate length, screw density, and plate material) were obtained for all participants. Multivariable analysis was performed using logistic regression to control for confounding in order to identify independent risk factors for nonunion. Results 28 of the 283 fractures were treated for nonunion, 13 were referred to us from other institutions. Obesity (BMI > 30), open fracture, occurrence of infection, and use of stainless steel plate were significant independent risk factors ( P Discussion Obesity, open fracture, occurrence of infection, and the use of stainless steel are prognostic risk factors of nonunion in distal femoral fractures treated with LLP independent of differing trends in how surgeons intervene in the management of nonunion.