Are routine postoperative dilations necessary after primary posterior sagittal anorectoplasty? A randomized controlled trial

Abstract Aim of the Study : For the past four decades, routine daily postoperative anal dilation by parents has been the standard treatment following a primary posterior sagittal anorectoplasty (PSARP). However, the clinical benefit of this practice has never been formally investigated. It is known that dilations can have a significant negative psychological impact on patients and families, and therefore, we aimed to study if routine dilations after a PSARP are necessary. Methods : A prospective, single institution randomized controlled clinical trial was conducted on patients with anorectal malformations (ARM) at our institution between 2017 and 2019. Patients were randomized to either a dilation or non-dilation group following their PSARP. Inclusion criteria included age less than 24 months and all patients undergoing primary repair of their ARM (except for cloaca). Patient characteristics, type of ARM, presence of colostomy, postoperative stricture, need for a skin level revision (Heineke-Mikulicz anoplasty (HMA), and need for redo PSARP were recorded. The primary outcome of the trial was stricture formation. The secondary outcome included strictures requiring interventions. A p-value of less than 0.05 was considered statistically significant. Institutional approval was obtained for this study and informed consents were obtained from all the patients. Results : 49 patients were included in our study. 5 (21%) in the dilation group and 8 (32%) in the non-dilation group developed strictures (p=0.21). Of these, 3 (13%) patients in the dilation group required HMA, and 4 (16%) patients in the non-dilation group required HMA (p=0.72). 4 patients required a redo operation for strictures: 2 in the dilation arm (these patients despite the plan to do dilations, chose not to do them consistently) and 2 in the non-dilation arm (p=0.59). Conclusion : Routine dilations after PSARP do not significantly reduce stricture formation. Based on these results, non-dilation is a viable alternative, and HM anoplasty remains a good back-up plan if a stricture develops.