Non-cutting setons for progressive migration of complex fistula tracts: a new spin on an old technique.

Aim: We introduced a modification of the loose seton for high transsphincteric fistula which involved daily self-rotation of the seton by 360°, which we call the progressive migration technique. The outcomes were evaluated.

Method: A retrospective review was undertaken of all operations for anal fistula performed by a single colorectal surgeon from Jan. 2002-Dec. 2007. Twenty-four patients with high transsphincteric fistulas were treated with loose, 0-silk setons. Patients were asked to rotate the seton daily, one revolution in each direction, pulling the knot through the fistula tract. Follow-up was done by phone with questionnaires to address incontinence pain scores, satisfaction, and recurrence.

Results: The patients' mean age was 48 years (range, 22-77 years), with M/F ratio of 3:1. The mean duration for seton in place was 14 months (range, 2-40 months). Follow-up ranged from 12-81 months (mean, 45 months). The progressive migration technique resulted in the gradual healing of the fistula tract in 75% of patients (n = 18), with no recurrence (setons completely worked their way to the surface [n = 9], or tract migration was extensive to allow a safe completion fistulotomy [n = 9]). All were fistula free. Twenty-five percent (n = 6) had Crohn's disease. Reported incontinence rates were 0% for solid and liquid stool and 8% (n = 2) for flatus. Twenty-five percent (n = 6) tolerated the setons poorly, and an alternative procedure was performed.

Conclusions: Simple daily self-rotation of a heavy silk seton, resulting in progressive migration of the fistula tract, is an alternative technique for treating complex, high transsphincteric anal fistulas.