Use of a 5-item modified Fragility Index for risk stratification in patients undergoing surgical management of proximal humerus fractures

HYPOTHESIS: We hypothesized that the modified Fragility Index (mFI) would predict complications in patients older than 50 years who underwent operative intervention for a proximal humerus fracture. METHODS: We retrospectively reviewed the American College of Surgeons National Surgery Quality Improvement Program database, including patients older than 50 years who underwent open reduction and internal fixation of a proximal humerus fracture. A 5-item mFI score was then calculated for each patient. Postoperative complications, readmission and reoperation rates as well as length of stay (LOS) were recorded. Univariate as well as multivariable statistical analyses were performed, controlling for age, sex, body mass index, LOS, and operative time. RESULTS: We identified 2,004 patients (median age, 66 years; interquartile range: 59-74), of which 76.2% were female. As mFI increased from 0 to 2 or greater, 30-day readmission rate increased from 2.8% to 6.7% (P-value = .005), rate of discharge to rehabilitation facility increased from 7.1% to 25.3% (P-value < .001), and rates of any complication increased from 6.5% to 13.9% (P-value < .001). Specifically, the rates of renal and hematologic complications increased significantly in patients with mFI of 2 or greater (P-value = .042 and P-value < .001, respectively). Compared with patients with mFI of 0, patients with mFI of 2 or greater were 2 times more likely to be readmitted within 30 days (odds ratio = 2.2, P-value .026). In addition, patients with mFI of 2 or greater had an increased odds of discharge to a rehabilitation center (odds ratio = 2.3, P-value < .001). However, increased fragility was not significantly associated with an increased odds of 30-day reoperation or any complication after controlling for demographic data, LOS, and operative time. CONCLUSION: An increasing level of fragility is predictive of readmission and discharge to a rehabilitation center after open reduction and internal fixation of proximal humerus fractures. Our data suggest that a simple fragility evaluation can help inform surgical decision-making and counseling in patients older than 50 years with proximal humerus fractures.