Beyond the Anastomosis: Is Pedicle Length the Critical Determinant of Thrombosis in Free Flaps?

Abstract This study aims to evaluate the effect of vascular pedicle length on arterial and venous thrombosis rates in free flap surgery. This retrospective study evaluated 546 patients who underwent free flap reconstruction with a single arterial and venous anastomosis between 2015 and 2024. Patients were categorized based on pedicle length (3–5, 6–8, and 9–15 cm). The relationship between pedicle length, anastomosis type, and thrombosis was analyzed using chi-square tests and multivariate logistic regression analysis. A total of 546 flaps were analyzed. The overall venous thrombosis rate was 10.1%, and the arterial thrombosis rate was 4.2%. A statistically significant relationship was found between increasing pedicle length and higher rates of venous thrombosis (5.8% for 3–5 cm, 8.3% for 6–8 cm, and 13.4% for 9–15 cm; p 0.05). Multivariate logistic regression on a patient subgroup confirmed that pedicle length was an independent predictor of thrombosis (p = 0.022), whereas anastomosis type was not (p = 0.986). Increased pedicle length is a significant and independent risk factor for venous thrombosis in free flap surgery. Surgeons should consider pedicle length a critical parameter during surgical planning to minimize thrombotic complications and improve flap survival rates. The study provides therapeutic, level III evidence.