The 5-Factor Modified Frailty Index Score Predicts Return to the Operating Room for Patients Undergoing Posterior Spinal Fusion for Traumatic Spine Injury

Objective: Within the trauma spine surgery literature, the effect of patient frailty on postoperative outcomes for posterior spinal fusion (PSF) remains clear. In this study, the authors quantified the influence of the 5-factor modified frailty index (mFI-5) score on hospital length of stay, diagnosis of a postoperative infection, 30-day readmission, and 90-day return to operating room (OR).

Methods: The authors retrospectively reviewed the records of all patients with traumatic spine injury undergoing PSF by a single surgeon at our institution from 2016 to 2021. Data were extracted using manual chart review and the mFI-5 score was calculated using data on comorbidities. Bivariate (Mann-Whitney U test and Fisher exact test) and multivariate regressions (linear and logistic) revealed whether there was an independent relationship between patient frailty and postoperative outcomes.

Results: The patient cohort included 263 patients (52.00 ± 19.04), 67 (25.5) were classified as frail, defined as having an mFI-5 score ≥2. Patients who were classified as frail were significantly more likely to have diabetes (odds ratio = 21.53; P < 0.001) and active cancer (odds ratio = 10.03; P = 0.004). Patients with mFI-5 scores ≥2 were also significantly older (P < 0.001) and had higher body mass index (BMI) (P = 0.007). Patients with mFI-5 scores >2 were more likely to return to the OR (odds ratio = 2.43; P = 0.037) on bivariate analysis. When controlling for demographics and clinical characteristics, mFI-5 score independently predicted return to OR (odds ratio = 1.294; P = 0.041).

Conclusions: Patient frailty independently predicted a return to OR in patients undergoing PSF for traumatic spine injury. Future studies can investigate methods for patient risk optimization to reduce morbidity and mortality.