Utility of Revised Risk Analysis Index as a Predictor of Mortality and Morbidity in Orthopaedic Trauma

Abstract

Objectives: The aim of this study was to determine the applicability of the Revised Risk Analysis Index (RAI-Rev) in orthopaedic trauma and compare the predictive discrimination for the RAI-Rev and the 5-Item Modified Frailty Index (mFI-5) for 30-day postoperative outcomes. Design: This is a retrospective cohort study. Setting: The American College of Surgeons National Surgical Quality Improvement database was used. Patient selection: All patients aged 18 or older who underwent surgical treatment for forearm, humerus, pelvis, acetabulum, femur, tibia, and hindfoot fractures from 2015 to 2020 were included. Outcome: 30-day postoperative mortality, major complications, and wound complications consisting of surgical site infection, and wound dehiscence were measured. Results: A total of 206,352 patients met inclusion criteria. The mean age was 69 years, with 64.2% (n = 132,514) being female. Multivariate regression analysis showed that increasing frailty tiers in both RAI-Rev and mFI-5 were independent predictors of mortality, major complications, readmission, and wound complications. The cohort with the highest degree of frailty in both RAI-Rev and mFI-5 had the greatest risk of poor outcomes. RAI-Rev had significantly superior predictive discriminatory thresholds compared with mFI-5 for predicting 30-day mortality (C-statistic: RAI-Rev [0.84] and mFI-5 [0.67], P < 0.001), major complications (C-statistic: RAI-Rev [0.73] and mFI-5 [0.65], P < 0.001), and readmission (C-statistic: RAI-Rev [0.68] and mFI-5 [0.63], P < 0.001). However, mFI-5 outperformed RAI-Rev when predicting wound complications (C-statistic: RAI-Rev [0.52] and mFI-5 [0.55], P < 0.001). Conclusion: The RAI-Rev tool demonstrated superior predictability of postoperative morbidity, mortality, and readmission rates compared with mFI-5 but was less effective in predicting surgical site complications. These findings demonstrate the utility of RAI-Rev in anticipating postoperative complications in the setting of orthopaedic trauma, where optimizing surgical candidate selection is not always possible. Assessing the predicted morbidity and mortality through RAI-Rev enables surgeons to accurately identify patients at high risk of complications, which can further research investigation to mitigate this risk.