Use of bulbospongiosus muscle for repair of traumatic posterior urethral stenosis combined with urethrorectal fistulas.

Abstract

To evaluate the efficacy and functional outcomes of bulbospongiosus muscle (BSM) flap interposition in the repair of urethral stenosis combined with urethrorectal fistula (USURF) or anterior rectal wall weakness (USRW). Between January 2016 and December 2023, 36 patients underwent transperineal posterior urethroplasty with BSM flap interposition. 36 patients with traumatic posterior urethral stenosis who underwent perineal urethroplasty without interposition of the BSM as the control group, matched by propensity score analysis during the same period. Pre- and intra-operative clinical data were collected. Functional outcomes, including voiding, erectile, and ejaculatory function, were compared between the two groups. A total of 36 males were included, of whom 19 (52.8%) had USURF and 17 (47.2%) had USRW. The mean follow-up time was 31.3 ± 17.7 months. The overall success rate was 94.4%. The median operating time was 3.0 (2.0, 3.0) h. The mean stricture length was 4.2 ± 1.2 cm. The mean postoperative maximum urinary flow rate was 24.2 ± 12.9 mL/s. Postoperative functional outcomes did not significantly differ between BSM interposition and BSM non-interposition group as assessed by Incontinence Questionnaire Male Lower Urinary Tract Symptoms (5.0 vs 3.0; P = 0.399), the International Index of Erectile Function 5 (3.0 vs 6.5; P = 0.183), Erection Hardness Score (P = 0.801), the Male Sexual Health Questionnaire 4 (1.0 vs 1.0; P = 1.00), European Quality of Life-5 Dimensions (0.9 ± 0.1 vs 0.9 ± 0.1; P = 0.139), EQ-VAS scores (75.9 ± 20.0 vs 79.9 ± 18.7; P = 0.428), urine dribbling (2.0 vs 1.5, P = 0.727), ejaculation volume (2.0 vs 2.0, P = 0.631) and ejaculation intensity (3.0 vs 4.0, P = 0.645). Transperineal BSM flap interposition combined with anastomosis urethroplasty and urethrorectal fistula repair is a safe and effective treatment. BSM can strengthen the anterior rectal wall and separate the urethral anastomosis from the repaired rectal fistula, which should improve the success rate of fistula repair.