Fistulectomy and primary sphincteroplasty (FIPS) to prevent keyhole deformity in simple anal fistula: a single-center retrospective cohort study.

OBJECTIVE

Fistulotomy remains the gold standard for the surgical treatment of simple anal fistula, but may cause fecal incontinence and a characteristic anal 'keyhole' deformity. Although seemingly trivial, keyhole deformity may lead to bothersome symptoms such as anal pruritus and fecal soiling. This study aims to evaluate the efficacy of fistulectomy and primary sphincteroplasty (FIPS), a technique with immediate sphincter reconstruction, in the treatment of simple anal fistula and the prevention of keyhole deformity created by simple fistulotomy.

METHODS

A retrospective study was performed on all consecutive patients who underwent FIPS for a simple anal fistula at our institution between January 2015 and August 2019. The primary outcome of the study was the rate of early postoperative wound dehiscence, which essentially transforms a FIPS into a simple fistulotomy and may lead to keyhole deformity. All patients received follow-up at regular intervals to evaluate fistula healing and the presence of keyhole deformity.

RESULTS

FIPS was performed in 24 patients (median age: 52.8 years). After a median follow-up time of 3.0 (2.0, 6.3) months, the overall healing rate was 95.8% (23/24 patients). Six (25%) patients experienced early postoperative wound dehiscence resulting in the development of a keyhole deformity. Five of them were symptomatic (mainly soiling). Keyhole deformity was diagnosed at a median time of 6.0 (3.8, 7.5) months postoperatively. The occurrence of early wound dehiscence and subsequent keyhole deformity was associated with a posteriorly located fistula ( = .02).

CONCLUSION

FIPS avoids the development of keyhole deformity in the majority of patients with simple anal fistula, but is less successful in posterior fistulas. Since FIPS is a very effective, fast and simple procedure, it should be considered a valid alternative for the treatment of every simple anal fistula.