Clinical utility of the modified frailty index in predicting adverse outcomes in patients undergoing lower extremity free flap reconstruction

Abstract

Background

Identifying at-risk patients for complications remains challenging in patients with chronic lower extremity (LE) wounds receiving free tissue transfer (FTT) for limb salvage. The modified-5 frailty index (mFI-5) has been utilized to predict postoperative complications, yet it has not been studied in this population. The aim of this study was to determine the utility of the mFI-5 in predicting adverse postoperative outcomes.

Methods

Patients ≥60 years, who underwent LE FTT reconstruction at a single institution from 2011 to 2022, were retrospectively reviewed. Patient characteristics, mFI-5, and postoperative outcomes were collected. Cohorts were divided by an mFI-5 score of <2 or ≥2.

Results

A total of 115 patients were identified, of which 71.3% (n = 82) were male, 64.3% (n = 74) had a mFI-5 score of ≥2, and 35.7% (n = 41) had a score <2. The average age and body mass index were 67.8 years and 28.7 kg/m², respectively. The higher mFI-5 cohort had lower baseline albumin levels (3.0 vs. 4.0 g/dL, p = .015) and higher hemoglobin A1c levels (7.4 vs. 5.8%, p < .001). The postoperative length of stay was longer in the higher mFI-5 cohort (18 vs. 13.4 days, p = .003). The overall flap success was 96.5% (n = 111), with no difference between cohorts (p = .129). Postoperative complications were comparable between cohorts (p = .294). At a mean follow-up of 19.8 months, eight patients (7.0%) underwent amputation, and 91.3% (n = 105) were ambulatory.

Conclusion

High microsurgical success rates can be achieved in comorbid patients with high frailty indexes who undergo FTT for limb salvage. A multidisciplinary team approach may effectively mitigate negative outcomes in elderly, frail patients.