FIPS vs LIFT for Fistula in ano- A double-blind randomized controlled trial(FILIP trial)

Ligation of intersphincteric fistula tract has gained popularity in the last ten years as sphincter preserving surgery for Fistula in ano.The success rate varies between 50-90% in different studies.The wide variation in success rate is attributed to variation in surgical techniques by the surgeons around the world.Another important cause of recurrence is a failure to identify the secondary tracts. Fistolotomy or fistulectomy is a gold standard procedure for low Fistula in ano, with minimal risk of incontinence and very low recurrence. However, for high Fistula in ano, this age-old procedure was not adopted because of the high incidence of faecal incontinence. The primary factor related to the incontinence is a division of fibres of the external sphincter. Combining sphincteroplasty to fistulotomy or fistulectomy has shown excellent outcome in some recent studies. The only significant drawback is the risk of incontinence. The rate of incontinence reported in littérature is as high as 16%.

In contrast, the rate of incontinence reported with LIFT is as low as 1.6%. However, our internal audit of patients operated for Fistula in ano by Fistulotomy and Primary sphincteroplasty(FIPS) have meagre incontinence rate and good outcome of over 90%. The incontinence observed in a few patients were mild and improved over time. Our success rate with LIFT in our setup is above 85% with minimal incontinence of 1%. No study has compared these two procedures. Hence, to determine the outcome and the incontinence rate with these two procedures, we propose this randomized controlled trial.