Utility of the modified 5-item frail index to predict complications and reoperations after hallux valgus surgery.

Introduction: The modified 5-item frailty index (mFI-5) has been recently proposed as a useful tool for predicting postoperative complications in orthopedic surgery. We aimed to analyze the utility of this score in predicting complications and reoperations after hallux valgus (HV) deformity surgery.

Methods: 551 patients undergoing percutaneous HV corrective surgery were retrospectively reviewed. The mFI-5 was calculated based and patients were categorized in three groups: (1) non-frail: patients without any of the 5 comorbidities, (2) pre-frail: patients with one comorbidity and (3) frail: patients with two or more comorbidities. Complications and surgical reoperations were recorded.

Results: In the study period 772 percutaneous surgeries were performed to correct hallux valgus deformity, 551 patients were included with a median age of 60 (IQR 48-70). 389 patients were non-frail (70.6%), 132 were pre-frail (23.9%) and 30 were frail (5.4%). 75 patients suffered complications (13.6%). Even though the rate of complications was higher in frailty patients (23.3%) compared with pre-frail (13.6%) and non frail (12.8%), no significant differences were observed among groups. 48 patients required reoperation (8.7%) but the rate of reoperations among frailty groups was not significantly different (p=0.11). Frailty patients had worse AOFAS scores at final follow up (p=0.011).

Conclusion: The mFI-5 was not useful to predict postoperative complications and reoperations after hallux valgus corrective surgery. Therefore, other factors should be considered when analyzing the risk of complications after HV corrective surgery.