Seton placement is a specialized medical intervention used to manage complex infectious tracts, known as fistulas, which are abnormal connections between two organs or an organ and the skin. The seton represents a standard and often necessary surgical technique for ensuring proper healing and preventing complications. This procedure is typically employed when a fistula tract involves delicate structures, such as the anal sphincter muscles, where traditional surgical removal could lead to serious functional impairment. The placement of this device is a foundational step in a staged treatment plan, allowing the body to manage infection safely before a definitive repair can be attempted.
Defining the Seton and Its Primary Function
A seton is a non-absorbable thread or flexible material, often made from silicone, nylon, or surgical suture, which is threaded through the entire fistula tract. Its primary purpose is to maintain continuous drainage of the infected tunnel, preventing the buildup of pus and infectious material that could lead to a recurring abscess. By keeping the tract open, the seton ensures that inflammation can subside and the tissues can begin to heal in a controlled manner. This continuous drainage is particularly important for fistulas that extend through the anal sphincter muscles.
Simple surgical closure of complex fistulas is frequently impossible due to the high risk of immediate recurrence and potential damage to the sphincter muscle. Cutting through a significant portion of the muscle to remove the tract could result in a permanent loss of bowel control. The seton acts as a wick, allowing the tract to decompress and mature without requiring a complete incision through the muscle tissue. This technique preserves the integrity and function of the muscle. The presence of the seton also encourages the formation of scar tissue, or fibrosis, around the tract, which helps stabilize the area for a subsequent procedure.
The Procedure for Seton Insertion
The placement of a seton is a surgical procedure performed in a hospital or outpatient setting, typically requiring general or regional anesthesia to ensure patient comfort and muscle relaxation. Pre-operative preparation often involves fasting for several hours and, for anal fistulas, may include using an enema to clear the lower rectum. These preparations help create a sterile field and allow the surgeon clear access to the internal opening of the fistula. The procedure itself is usually brief, often lasting less than an hour, and most patients are discharged home the same day.
The surgeon first identifies both the internal and external openings of the fistula tract using a probe. Once the tunnel is mapped, the seton material is threaded through the tract, entering one opening and exiting the other. The two ends are then secured outside the body, usually by tying them together to form a loop. This external knot holds the seton in place, creating a continuous loop that spans the entire fistula. The placement confirms that the tract is fully open and draining, establishing conditions for long-term management.
Living with a Seton
The immediate post-operative period will involve some discomfort, which is managed with prescribed pain medication and over-the-counter anti-inflammatories. Patients are strongly encouraged to use stool softeners and maintain a high-fiber diet to prevent constipation, as straining during bowel movements can cause pain and pressure on the surgical site. A small amount of drainage, which may be pus, blood, or serous fluid, is expected and is a sign that the seton is functioning correctly.
Managing the drainage requires consistent hygiene, often involving the use of small gauze pads or sanitary liners to protect the surrounding skin and clothing. Sitz baths, where the patient soaks the area in warm, shallow water, are highly recommended three to four times a day. These soaks help keep the area clean, soothe inflammation, and promote blood flow to the tissues. The seton itself needs to be gently cleaned or “flossed” daily, a technique the medical team will demonstrate, to prevent debris from blocking the drainage path.
Once the initial post-operative healing occurs (typically one to two weeks), the seton should not significantly interfere with daily life. While strenuous activity should be avoided initially, most people can return to work, exercise, and normal activities, including bathing and sexual activity. Patients must remain vigilant for signs of complication, such as increased pain, fever, or a sudden change in the amount or consistency of the drainage.
Different Seton Types and the Removal Process
Setons are generally categorized based on their function in the overall treatment plan: draining or cutting. Regardless of the type used, the seton itself is rarely the final cure; it is a staged treatment that prepares the tract for eventual removal or a subsequent procedure.
Draining Seton
A draining seton, also known as a loose seton, is tied loosely to serve solely as a conduit for infection and inflammation to resolve. This type is typically left in place for weeks or months to stabilize the area and prepare the tissues for a later, definitive surgical repair, such as a flap procedure.
Cutting Seton
A cutting seton, sometimes referred to as a tightening seton, is used less commonly and is designed to slowly work through the muscle tissue over time. This type is periodically tightened in the surgeon’s office, gradually cutting through the fistula tract while simultaneously promoting scar formation behind it. This slow process allows the muscle to heal as the seton advances, minimizing the risk of permanent sphincter damage.