Purpose/Background: Although fistulotomy has been the mainstay of treatment of fistula-in-ano (FIA), fear of resulting fecal incontinence (FI) has prompted the emergence of sphincter-sparing techniques that may result in higher recurrence. This study aimed to compare long-term risks of FI and recurrence following sphincter- sparing and non-sphincter-sparing procedures for FIA.

Methods/Interventions: After institutional review board approval, all patients with FIA managed operatively between 2000-2012 by colorectal surgeons at a tertiary center were included. Patients with inflammatory bowel disease, pelvic radiation, and non-definitive procedures were excluded. Medical records/operative reports were reviewed. Patients were contacted by telephone to document FI using the Cleveland Clinic Florida-Fecal Incontinence Score (CCF-FIS) and Fecal Incontinence Quality of Life (FIQL) scale. Fistulas were characterized by type, location, branching, number of internal openings, classification as high or low, and primary or recurrent fistula. Procedures were classified as sphincter-sparing [≥1 of fibrin glue, anal plug, anorectal flap, ligation of intersphincteric fistula tract (LIFT)] or non-sphincter-sparing [fistulotomy, cutting seton].

Results/Outcome(s): Of 338 patients, 156 were available for long-term follow-up: 119 (76.3%) and 37 (23.7%) had non-sphincter-sparing and sphincter-sparing procedures, respectively. Median follow-up was 9.1 years (6.5, 12.6). The proportion of females was similar in sphincter-sparing and non-sphincter-sparing groups (29.7% vs. 20.2%, p=0.223). The sphincter-sparing group had fewer referred recurrent (5.4% vs. 29.4%, p=0.003) and posterior (27.0% vs. 52.1%, p=0.008) fistulas, but more high fistulas (73.0% vs. 15.1%, p<0.001). No patients with sphincter-sparing surgery had FI vs. 21 (17.6%) with non-sphincter-sparing procedures who did (CCF-FIS range 0-15, median 0), 2 (1.7%) of whom had moderate-to-severe symptoms (CCF-FIS score ≥10). Median FIQL scores (range 1-4; 4=not affected) were lifestyle 4.0 (2.0-4.0); coping 4.0 (1.33-4.0); depression 4.0 (1.30-4.0); embarrassment 4.0 (1.33-4.0). Fistula recurrence was significantly greater in sphincter-sparing procedures (59.5% vs. 19.3%, p<0.001). After adjusting for follow-up, high fistula, and posterior location on multivariate analysis, sphincter-sparing procedures were associated with higher odds of recurrence vs. non-sphincter sparing procedures (OR=5.72 [95%CI 2.02-16.17]). Non-primary fistula was a predictor for recurrence after repair in both groups (OR=2.73 [95%CI 1.08-6.90]).

Conclusions/Discussion: Sphincter-sparing procedures had significantly higher recurrence rates vs. non- sphincter-sparing procedures. Long-term rates of significant FI after non-sphincter-sparing procedures were low and did not impact quality of life, indicating that these procedures remain a safe option with appropriate patient selection.

Should We Be Quick To Dismiss Non-Sphincter-Sparing Surgery for Fistula-in-Ano: An Analysis of Long-Term Outcomes