Ano-rectovaginal fistula after obstetrical anal sphincter injury: Diverting stoma does not improve the surgical results.

Aim: Ano-rectovaginal fistulas (ARVF) are challenging for the surgeon. Most of the series mix aetiologies, leading to confusion with respect to the conclusion. The aim of this study was to assess the factors associated with the success of ARVF management following obstetrical anal sphincter injury (OASIS).
Methods: This retrospective multicentric study included all the patients undergoing surgery for ARVF identified by the hospital codes. Patients for whom the aetiology of ARVF was not OASIS were excluded. The major outcome measure was the success of the procedure.
Results: Sixty patients with treated ARVF due to OASIS were identified. The success of overall management was 91.7%. Female patients underwent a mean of 2.5 (±1.7) procedures. A diverting stoma was formed in 29 patients (48.3%) of which 26 were closed at the end of the management period (89.7%). Of the 148 surgical procedures, only 55 were successful (37.2%). The order of the procedures (OR = 1.38; 95% CI: 0.75-2.51) or the diverting stoma (OR = 1.46; 95% CI: 0.31-6.91) were not significantly associated with the success of the surgery. However, Martius flap (OR = 4.13; 95% CI: 1.1-15.54) and Musset procedures (OR = 5.79; 95% CI: 1.77-18.87) produced better results than the endorectal advancement flap (ERAF). The other procedures did not show a significant correlation with management success.
Conclusion: A diverting stoma is not mandatory in the management of ARVF due to OASIS to improve the success of the surgical procedure. While the Martius flap procedure offers better results, the ERAF procedure may be preferred as a primary intervention in the absence of sphincter injury as it is less invasive. In cases of residual sphincter injury, the Musset procedure is most likely to be the best option.
(© 2022 The Authors. Colorectal Disease published by John Wiley & Sons Ltd on behalf of Association of Coloproctology of Great Britain and Ireland.)