Comparison of frailty and other risk indices in prediction of perioperative complications following surgical intervention for proximal humerus fractures

Aims: Proximal humerus fractures (PHFs) often occur in a population at risk for complications following surgery. The purpose of this study is to assess the associations of frailty with complications of surgical intervention for PHFs. Methods: The American College of Surgeons National Surgical Quality Improvement Program database was queried from January 2015 to December 2020 for patients aged ≥ 60 years who were undergoing surgery for PHFs. Tiered frailty scores were calculated by the revised risk analysis index (RAI-Rev) and the modified five-term frailty index (mFI-5) factor. Outcomes included 30-day mortality, readmission, length of stay, and complications. Analysis of variance and binary logistic regression were used to assess associations with odds ratio (OR) and 95% CI. Discriminatory accuracy was quantified by receiver operating characteristic curve analysis and C-statistics. Results: A total of 6,020 patients with PHFs underwent surgical intervention (51% frail or severely frail). The use of reverse total shoulder arthroplasty (rTSA) for PHFs increased over time (OR 1.14 (95% CI 1.11 to 1.18)), whereas all other procedures decreased. Frail patients were more likely to experience a complication after surgery (OR 2.92 (95% CI 2.48 to 3.43)). Overall, rTSA had higher rates of complications (17% (OR 0.93 (95% CI 0.86 to 0.99)) and non-home discharge (32% (OR 0.84 (95% CI 0.79 to 0.90)). However, these decreased from 2015 to 2020. The RAI-Rev had superior predictability to mFI-5 for any complication (area under the curve (AUC) 0.674 vs 0.601), postoperative blood transfusion (AUC 0.704 vs 0.618), and non-home discharge (AUC 0.778 vs 0.637). Conclusion: Frail patients have a three-times higher 30-day complication risk following proximal humerus surgery. rTSA is associated with higher rates of complications compared with internal fixation, but has steadily narrowed the gap over time. While the long-term outcomes and functional benefit should be considered, preoperative frailty assessment can be predictive of perioperative complications and disposition in this population.