What it is

What is a Fistulotomy?

A fistulotomy is the most common and effective surgical procedure for treating a simple anal fistula. The term means to 'open the fistula'. The procedure involves identifying the fistula tract and then carefully incising the overlying tissue, including skin and a portion of the anal sphincter muscle, to lay the tract open. This converts the subcutaneous tunnel into an open wound, which then heals from the inside out over a period of several weeks. The primary goal is to completely eradicate the fistula tract while preserving enough sphincter muscle to maintain fecal continence.

Am I a candidate?

Who is a Good Candidate for a Fistulotomy?

A fistulotomy is the gold standard treatment for simple anal fistulas. An anal fistula is considered simple if its tract crosses less than 30% of the external anal sphincter (low transsphincteric), only involves the internal sphincter (intersphincteric), or is superficial and does not involve the sphincter complex at all (subcutaneous). These types of fistulas can be safely opened without a significant risk of compromising continence. The procedure is not recommended for complex fistulas that involve a large portion of the sphincter muscle, as this would carry an unacceptably high risk of incontinence.

How it's done

1Under anesthesia, a thin probe is gently passed through the fistula tunnel to map exactly where it runs.

2The tissue over the tunnel — which for a simple fistula includes at most a small, safe portion of the sphincter muscle — is divided, turning the closed tunnel into a shallow open groove.

3The tract is cleaned of infected tissue.

4The wound is left open on purpose, so it heals from the bottom up and the fistula can't re-form over trapped infection.

5Most patients go home the same day.

What to expect

Same day

Home once the anesthesia wears off, with a small dressing.

First few days

The sorest stretch. Warm sitz baths after bowel movements do more for comfort than anything else. Keep stools soft with fiber and fluids.

About a week

Most patients are back to desk work and non-strenuous activity.

Weeks 2–8

The open wound fills in from the bottom up. Some drainage and spotting is normal; complete healing commonly takes six to eight weeks.

Follow-up

Wound checks to make sure it heals from the base up rather than sealing over too early.

Risks & considerations

What are the Risks?

While a fistulotomy is a very effective and safe procedure for simple fistulas, it is not without risks. These include:

Pain: Postoperative pain is expected and is usually managed with sitz baths, stool softeners, and oral pain medications.
Bleeding: Minor bleeding or spotting is common, particularly with bowel movements. Significant bleeding is rare.
Infection: A wound infection can occur, but it is uncommon.
Fecal Incontinence: This is the most significant potential risk. While minor incontinence to gas or slight soiling is reported in some studies, major incontinence is rare when the procedure is performed on appropriately selected patients with simple fistulas. The risk increases with the amount of sphincter muscle that is divided.
Recurrence: The fistula can recur if the tract is not completely laid open or if there are unidentified secondary tracts.