How is Seton[Thread] treatment done and what are disadvantages of this procedure?

A seton or thread is a loop of flexible material which is placed along the fistula track to maintain drainage for a period of time. It create scar tissue around part of the sphincter muscle before it is cut with a knife


  • Loose seton- In this method, the seton is placed to maintain drainage and create scar tissue around the sphincter so that it’s edges don’t retract after cutting.
  • Cutting seton- In this method, the seton is tightened gradually over regular intervals so that it slowly cut all the way through the muscle over the course of several weeks .


  • Less-invasive- The procedure involves less cutting though the final scarring is comparable to Fistulotomy.
  • Less pain- The pain in this procedure is less compared to Fistulotomy.
  • Combined with other procedures- In complex fistulas ,this procedure can be combined with other procedures.


  • Long follow up-The patient need to come for repeated follow-up visits especially in cutting variety.
  • High risk of Incontinence in

– Anterior fistulas in female patients with a history of vaginal delivery

– High trans-sphincteric and complex fistulas [ 30-50% incidence of incontinence to flatus or liquid by seton usage in complex fistulas- Joy et al- Colorectal Dis. 2002]