Delayed secondary repair of third- and fourth-degree obstetric anal sphincter injuries: a randomized controlled trial comparing overlapping versus end-to-end sphincter repair

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• Picked for Obstetrics and Gynecology (top studies of the week, 9 August 2026).

Abstract

BACKGROUND: Secondary anal sphincter repair is necessary in fewer than 3% of cases following primary repair of obstetric anal sphincter injuries (OASI). Although there is some growing evidence comparing early and delayed secondary repairs, the traditional and most common way to manage secondary OASI is still delayed repair. This study compared clinical and functional outcomes of overlapping versus end-to-end sphincter repair techniques in delayed secondary repair of OASI. METHODS: In this single-center randomized controlled trial, 40 women with third- or fourth-degree OASI and wound dehiscence after primary repair were randomized 1:1 to overlapping sphincteroplasty or end-to-end approximation. Assessments were performed preoperatively and at 2 weeks, 3, 6, and 12 months. The primary outcome was the Wexner incontinence score at 12 months. Analysis was per-protocol with intention-to-treat sensitivity analysis. RESULTS: Thirty-eight women were included in the per-protocol analysis (overlapping n = 18; end-to-end n = 20). Two patients in the overlapping group were lost to follow-up. Operative time was significantly longer in the overlapping group (121.3 ± 5.5 vs 102.8 ± 6.3 min; p < 0.001). The overlapping repair resulted in a significantly lower mean Wexner score (0.5 ± 0.2 vs 2.2 ± 0.8; p < 0.001) and higher rate of complete continence (Wexner ≤ 5: 100% vs 85%; p = 0.03). Time to wound healing was shorter (23.3 ± 4.8 vs 26.9 ± 5.5 days; p = 0.08) and overall complications were lower (11.1% vs 30.0%) in the overlapping group. Endoanal ultrasound Starck scores and manometry parameters showed consistent trends favoring overlapping repair, although these differences were not statistically significant. CONCLUSION: In delayed secondary OASI repair, overlapping sphincteroplasty provided superior continence outcomes and lower complication rates than end-to-end repair, when combined with meticulous muscle mobilization and a standardized postoperative regimen. These findings support overlapping repair as the preferred technique in this setting.

Abstract as published, via PubMed.