Routine Use of Setons for the Treatment of Anal Fistulae


Aim : Anal fistula is usually treated by either fistulotomy or fistulectomy. We described the routine use of setons to treat anal fistula without any surgery.

Method : Forty-seven consecutive patients with diagnosed anal fistulae were treated using setons alone.

Results : The median age of the patients was 41 (range: 18-70). Of the 47 patients, 15 had surgery previously for fistula and perianal abscess. At least two setons were inserted through each fistula. One was tied tightly to function as a cutting seton and this was sequentially tightened by the patient and another was tied loosely for drainage. Of the 47 patients, 33 (70%) had the placement of setons in the clinic without any anaesthesia. The remaining 14 patients had the setons inserted in the operating room, with one patient having a complex anal fistula and 13 patients having perianal abscess requiring drainage at the same time. There were no post procedure complications in the series. Forty-one patients had completed follow up at clinic within a median duration of 15 weeks (range: two to 67 weeks). The fistula was completely healed by this method in 37 patients (78%). The median healing time was nine weeks (range: four to 62 weeks). One patient developed recurrent fistula and was healed after another seton placement. No patient developed any faecal incontinence and all patients were satisfied with this treatment.

Conclusion: The routine seton method is safe, cheap and effective in the treatment of anal fistula regardless of type. It does not leave an open wound and most patients are satisfied with the treatment.

Keywords: fistula, transphincteric, intersphincteric, seton, treatment.


Fistula-in-ano is a common perianal condition that is associated with appreciable morbidity and inconvenience to the patient. The morbidity increases with the more complex or high type of fistulae. The most notable classification of fistula type is by Park's and this is based on the relationship between the fistula track and the anal sphincters (1). However, the complexity and the relevance of this classification raise doubts of its use in the routine management of anal fistula.

The principles of anal fistula surgery are to eliminate the fistula, prevent recurrence and preserve sphincter function. Success is usually determined by identification of the primary opening and dividing the least amount of sphincteric muscle possible. Most of the anal fistulae have been conventionally treated by either fistulotomy or fistulectomy, which have proven to be effective (2). However, the procedure requires local, regional or general anaesthesia. Post-operative wounds are usually left open and take much time to be completely healed through secondary intention. Furthermore, there exists a noticeable risk of recurrence and incontinence especially in high risk patients with complex or high fistulas, women with anterior fistulas and elderly patients (2).

Setons have been used to manage anal fistula for hundreds of years. In the literature, setons were commonly described only for the high or complex anal fistula in order to avoid faecal incontinence and recurrence'3'. The usage of this method was deemed cumbersome and too slow.

In this study, we have described the initial results of the routine use of the two setons placement method, comprising one drainage seton and another primary cutting seton, for all consecutive patients with any type of anal fistulae in the outpatient clinic.


A prospective series of 47 consecutive patients with anal fistula managed by seton placement between July 1997 to December 2000 was studied.