The goal of this study was to compare the outcomes of advancement flap (AF) versus fistulotomy with sphincter reconstruction (FSR) for primary complex fistula-in-ano in terms of recurrence and anal function.

A randomized clinical trial was conducted to compare AF with FSR. Preoperative and postoperative evaluation included physical examination, anal ultrasonography, and anal manometry, with a minimum follow-up period of 24 months. Anal continence was evaluated using the Wexner Continence Grading Scale (scale, 0–20).

Sixty patients were randomized to AF (group 1, N = 30) or FSR (group 2, N = 30). Three patients from group 1 and 2 patients from group 2 were excluded from the study because of active sepsis at surgery. Fistulas were classified as high transsphincteric in 44 patients (80%) and suprasphincteric in 11 patients (20%). Demographic and clinical features showed no differences between the 2 groups. The mean Wexner Continence Grading Scale did not vary significantly after surgery in either group, and there was no difference between the groups. On anal manometry there was a significant decrease in the maximum resting pressure after surgery in both groups, and in the maximum squeeze pressure in the AF group, but neither the maximum resting pressure nor the maximum squeeze pressure differed significantly between groups, either before or after surgery. Two fistulas from each group recurred after surgery (7.4% and 7.1%, respectively). The mean follow-up period was 36 months (range, 24–52 mo).

FSR compares with AF in terms of postoperative continence and recurrence. Anal continence and manometric values are not jeopardized in either technique.