Surgery
Anal Fistula Surgery
Anal fistula surgery treats an abnormal small tunnel between the anal canal and the skin near the back passage.
Quick answer
Anal Fistula Surgery: what it is, why it's done and what happens
An anal fistula is a small channel that develops between the inside of the anal canal and the skin nearby, often after an abscess. Surgery aims to close or drain it, using techniques such as fistulotomy or a seton (thread).
- Why it is done: It is used to treat an anal fistula causing pain, discharge, recurrent abscesses or irritation, as fistulas rarely heal on their own and can keep causing problems.
- What happens: Under general anaesthetic, the surgeon either opens the tunnel to let it heal (fistulotomy) or places a seton thread to drain it and protect the muscle, depending on how the fistula relates to the anal muscles.
What it is
An anal fistula is a small channel that develops between the inside of the anal canal and the skin nearby, often after an abscess. Surgery aims to close or drain it, using techniques such as fistulotomy or a seton (thread).
Why it is done
It is used to treat an anal fistula causing pain, discharge, recurrent abscesses or irritation, as fistulas rarely heal on their own and can keep causing problems.
What happens
Under general anaesthetic, the surgeon either opens the tunnel to let it heal (fistulotomy) or places a seton thread to drain it and protect the muscle, depending on how the fistula relates to the anal muscles.
Recovery
The area is usually sore for a couple of weeks, with dressings and salt baths aiding healing. Simple fistulas often heal within weeks, while complex ones may need staged treatment over months.
Good to know
Risks and things to consider
The main concern is protecting the anal sphincter muscles to preserve bowel control. Risks include bleeding, infection, recurrence and, if muscle is affected, some change in continence.
Education and reference only. This explains the procedure in general terms and is not medical advice. Your own care, risks and recovery will be explained by the team looking after you.
Answers
Anal Fistula Surgery: frequently asked questions
What is a seton?
A seton is a soft thread passed through the fistula to keep it draining and prevent abscesses while protecting the anal muscles. It is often used for complex fistulas, sometimes before further treatment.
Can an anal fistula come back after surgery?
Yes, especially with more complex fistulas or underlying conditions such as Crohn’s disease. Some people need more than one procedure to achieve lasting healing.
Related
Other surgery
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — procedure and treatment guidance
- Relevant Royal College / professional body
Building patient-education content for procedures?
We create clear, accurate, referenced medical explainers and decision aids for teams and learners.