Comparative effectiveness of sphincter-sparing and non-sphincter-sparing procedures for complex anal fistulas: A systematic review and network meta-analysis of postoperative incontinence, pain, and quality of life.

BACKGROUND

In complex anal fistulas, treatment should achieve healing while preserving continence and quality of life. However, direct comparative evidence across sphincter-preserving, sphincter-dividing/reconstructive, and seton-based approaches remains limited. We compared these techniques for postoperative fecal incontinence, pain, quality of life, and recurrence.

METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Network Meta-Analysis checklist to report our study. We searched PubMed, Embase, and CENTRAL until August 2025. We included randomized controlled trials and nonrandomized controlled trials in adults with complex cryptoglandular anal fistulas. We extracted data via Research Electronic Data Capture and performed risk-of-bias evaluation via Risk of Bias 2/ROBINS-I. We performed data analysis using MetaXL with setonas the reference technique. We used Grading of Recommendations Assessment, Development, and Evaluation to rate the certainty of our evidence.

RESULTS

We included 2,972 patients across 43 studies. For fecal incontinence, adipose-derived stem cells plus fibrin glue and video-assisted anal fistula treatment combined with ligation of the intersphincteric fistula tract showed the most consistent reductions compared with seton (moderate-high certainty). For pain, the JUMP seton technique (described by Khoshnevis et al) and video-assisted anal fistula treatment combined with ligation of the intersphincteric fistula tract were associated with lower pain scores (moderate certainty). Soluble N-ethylmaleimide-sensitive factor attachment protein receptor, video-assisted anal fistula treatment combined with ligation of the intersphincteric fistula tract, and ligation of the intersphincteric fistula tract plus platelet-rich plasma showed higher quality-of-life scores compared with seton (moderate certainty). Recurrence was lower with adipose-derived stem cells plus fibrin glue (relative risk, 0.02) and acellular dermal matrix (relative risk, 0.08) compared with seton. Randomized controlled trial-only sensitivity analyses were consistent with low inconsistency.

CONCLUSIONS

Ligation and adhesive-based approaches showed an advantage over seton-based techniques in terms of fecal incontinence, pain, and quality-of-life results with comparable recurrence rates. These results highlight the importance of careful patient selection and choosing specific surgical approaches to improve patients' outcomes.