Seton Placement

Seton placement is a surgical procedure to treat an anal fistula. An anal fistula is an abnormal tunnel that forms between the inside of your anus (butthole) and the skin around it. These fistulas usually develop after an infection causes a pocket of pus (abscess) to form.

A seton is a thin piece of surgical material that your healthcare provider places through the fistula tunnel. The seton keeps the tunnel open so it can continue to drain. This helps reduce infection and inflammation. It also lowers the risk of another abscess forming.

Your provider may recommend seton placement if you have a complex anal fistula or a fistula that involves your anal sphincter muscles. These are the muscles that control your ability to hold in your poop.

Healthcare providers often use this type of fistula repair surgery as a bridge before you have other procedures. After the infection improves, they can remove the seton and close the fistula. In some cases, a seton can stay in place long term to help manage symptoms.

Benefits and risks

One of the main benefits of seton placement is that it allows the area to heal while protecting your anal sphincter muscles. Your provider may be able to keep the muscles intact. This can help you avoid being unable to control your bowel movements (fecal incontinence). Seton placement may also:

• Ensure constant drainage of pus and fluids
• Reduce pain and swelling
• Prevent new abscesses from forming
• Prepare the fistula for future treatment

Complications that can occur with a seton include:

• Ongoing pain, discomfort or soreness
• Skin irritation
• Bleeding
• Infection
• Continued drainage from the fistula
• Return of the fistula

What happens during this procedure?

Before seton placement surgery, you’ll get anesthesia so you won’t feel any pain.

Your surgeon will locate the internal and external openings of the fistula. They may use a small probe to trace the fistula’s path. Once your surgeon finds the tunnel, they’ll do one of two types of seton placement:

• Draining seton: Your surgeon will pass a thin piece of thread or rubber (seton drain) through the fistula tunnel. They’ll place the seton tight enough to stay in position but loose enough to let draining continue. Then, they’ll tie it in a loop. A seton drain keeps the fistula open while waiting for the infection to improve.
• Cutting seton: Your surgeon will make a cut in the skin between the internal and external fistula openings. They’ll place a small piece of braided silk or elastic through the fistula tunnel. Then, they’ll secure it snugly around your anal sphincter. You’ll have the seton retightened regularly to slowly cut through the fistula over time.

Seton placement is an outpatient procedure. That means you’ll likely go home the same day. The procedure typically lasts 30 to 60 minutes, but the length of time depends on how complex the fistula is.

Seton placement recovery

Most people recover at home after seton placement.

Some minor pain, swelling and drainage from the fistula are normal while the seton is in place. Your healthcare provider will:

• Recommend over-the-counter (OTC) pain medication
• Encourage warm sitz baths
• Show you how to keep the area clean during healing

Follow-up care

Your provider will schedule follow-up appointments to check healing and make sure the seton is working correctly.

Your provider will also advise you to:

• Eat foods high in fiber.
• Drink plenty of fluids.
• Avoid heavy lifting for a short time.

How long do seton drains stay in?

How long the seton stays in place depends on your treatment plan. Some people have another fistula repair surgery several weeks or months later. Others may keep a seton drain in place long term.

When should I call my healthcare provider?

Contact your provider if you have:

• Fever or chills
• Increasing pain
• Heavy bleeding
• Increased swelling around your anus
• Signs of a new abscess or infection

Is seton placement a cure for an anal fistula?

Not always. Healthcare providers often use a seton to control infection and keep the fistula draining while the area heals. For many people, seton placement is one step in a larger treatment plan that may include another procedure later.

Will I be able to poop with a seton?

Yes. A properly placed seton shouldn’t prevent you from pooping. You may notice some drainage or mild discomfort, especially early in recovery.