Abstract
BACKGROUND: Free anterolateral thigh flap (ALT) surgery is critical for managing extremity soft tissue defects, but postoperative complications limit its broader application. This study aimed to develop a nomogram to predict the risk of postoperative complications following ALT surgery, improving postoperative management. METHODS: This retrospective cohort study included 909 patients who underwent ALT surgery from January 2016 to January 2024. Patients were divided into a development group (606) and a validation group (303). Multivariable logistic regression identified independent predictors of complications, which were incorporated into a nomogram. The predictive performance was evaluated using the concordance index (C-index) and receiver operating characteristic (ROC) curve analysis. RESULTS: Independent risk factors for complications included vascular crisis, incomplete hemostasis, improper vascular anastomosis, flap length, flap length-to-width ratio, and prolonged surgery time. The nomogram demonstrated excellent predictive accuracy, with AUCs of 0.910 and 0.965 in the development and validation groups, respectively. CONCLUSION: We developed a nomogram that accurately predicts the risk of postoperative complications in ALT flap surgery, helping clinicians assess patient risk and tailor treatment strategies.