Tract Length Predicts Successful Closure With Anal Fistula Plug in Cryptoglandular Fistulas

Abstract

Collagen anal fistula plug treatment of transsphincteric fistulas produces variable results. The purpose of our study was to determine whether long-tract fistulas (>4 cm) correlated with successful closure. All patients undergoing transsphincteric cryptoglandular fistula repair with anal fistula plugs were enrolled in a prospective database. Patients with Crohn's disease were excluded. Fistula tract length was measured intraoperatively by subtracting the remaining plug length from the original plug size. All procedures used standardized techniques and postoperative care pathways. The primary outcome was complete fistula closure assessed through both postoperative outpatient visits and a follow-up telephone questionnaire. Forty-one patients with 42 fistula tracks were enrolled over a 39-month period. Complete closure was achieved in 18 of 42 (43%) fistulas at a mean follow-up of 25 months. Closure was not associated with gender, age, tract location, duration of seton, or length of follow-up. Successful closure was significantly associated with increased tract length, because fistulas longer than 4 cm were nearly 3 times more likely to heal compared with shorter fistulas ((14/23, 61%) vs (4/19, 21%), P = .004; relative risk = 2.8; 95% CI 1.14-7.03). Anal fistula plug repair of cryptoglandular anorectal fistulas is more successful for long-tract fistulas. Although the overall success is modest, limiting surgical indications to fistulas exceeding 4 cm may maximize benefits of the plug technique.