A cover flap reduces the rate of fistula after urethroplasty whatever the severity of hypospadias.

OBJECTIVE To determine which patients should benefit from the interposition of a well-vascularized flap between the neourethra and the penile skin and if it should be performed even in mild hypospadias. PATIENTS AND METHODS A retrospective study on patients with a primary hypospadias repair was performed (2003-2017). Only patients undergoing urethroplasty based on the principle of a tubularization were selected to ensure comparable groups. Patients were assigned in two groups according to the use or not of a cover flap. Univariate analysis and adjusted logistic regression were used to evaluate the relation between postoperative complications, the severity of hypospadias, the use of flap and patients' characteristics. RESULTS Three-hundred and seventy-six patients were included with anterior (59.3%), midshaft (27.4%) and posterior hypospadias (13.3%). The median follow-up was 54 months (24 months-17 years). The overall rate of fistula was 11.7% (n = 44). Comparing the outcome in children with flap (n = 217) to controls (n = 159) showed that the use of a flap reduces the rate of fistula (6.5 vs 18.9%, p < 0.001). Stratification of the study according to the phenotype reveals that the more severe the hypospadias, the more protective was the flap (OR = 2.6 for anterior, 5.5 for midpenile, 7.1 for posterior hypospadias). The flap remains nevertheless significantly effective whatever the phenotype (p < 0.05 for anterior, p = 0.01 for midpenile, p = 0.02 for posterior hypospadias). CONCLUSIONS The more severe the hypospadias, the more effective is the cover flap to avoid fistula. It remains nevertheless suitable even in anterior hypospadias and the use of a cover flap should not be limited to the surgery of severe phenotypes.