Fistula plug: does it work

At a glance

The fistula plug is a sphincter-preserving approach to treating anal fistulas. It involves placing a biological scaffold into the fistula tract, which the body’s tissue then grows into, potentially closing the tunnel. The appeal is straightforward: no cutting, no wound, no sphincter damage.

The reality is more nuanced. Success rates are variable and generally lower than other fistula procedures. This guide examines what the plug is, how it works, and what the realistic expectations are.

How it works

The fistula plug is a cone-shaped device made from biological material — typically extracellular matrix derived from porcine (pig) intestinal submucosa. It is biocompatible and designed to be gradually absorbed by the body as new tissue grows in its place.

The procedure

1. The fistula tract is cleaned and prepared
2. The plug is drawn through the tract from the internal opening
3. The wide end of the cone sits at the internal opening; the narrow end at the external
4. The plug is secured with sutures
5. The body’s tissue gradually infiltrates the plug, ideally closing the tract

The procedure is typically done as a day case. Recovery is usually quick, with minimal pain.

Success rates — the honest picture

The fistula plug has had a mixed reception in the surgical literature:

• Early studies reported success rates of 60 to 80 percent or higher
• Larger, more recent studies tend to report success rates of 20 to 50 percent
• The most common reason for failure is plug extrusion — the plug falling out before the tissue has had time to grow into it

The variability in reported success rates makes this one of the harder fistula procedures to evaluate. Your surgeon’s personal experience with the plug is likely the most useful data point.

Advantages

• Sphincter preservation: no muscle is cut, so continence risk is effectively zero
• Minimal wound: no open wound to manage
• Quick recovery: most people return to normal activities within days
• No bridge burning: if the plug fails, the fistula is in its original state and all other surgical options remain available
• Repeatable: the procedure can theoretically be attempted more than once

Disadvantages

• Variable success rates: lower than fistulotomy and often lower than LIFT or advancement flap
• Plug extrusion: the most common complication — the plug falls out before healing
• Cost: the biological material adds cost to the procedure
• Not universally available: not all surgeons offer or recommend it
• Limited to certain fistula types: not suitable for very short, very wide, or actively infected tracts

Who it may be suitable for

The fistula plug is most commonly considered for:

• Transsphincteric fistulas where sphincter preservation is a priority
• Patients who want to try a low-risk option before considering more involved surgery
• Simple fistulas with a well-defined, clean tract
• Situations where other sphincter-preserving options have been tried or are not suitable

The balanced view

The fistula plug is an option — not the primary recommendation for most fistulas, but a reasonable consideration in specific situations. Its appeal lies in its low-risk profile and the preservation of future options. Its limitation is a success rate that is lower and less predictable than other procedures.

Discussing the plug with your surgeon in the context of your specific fistula — its anatomy, its history, and your priorities — is the way to determine whether it is worth trying.