Randomized clinical trial comparing a small intestinal submucosa anal fistula plug to advancement flap for the repair of complex anal fistulas

Introduction: Current treatments for complex anal fistulas are associated with substantial variability in healing, recurrence, and incontinence rates. This study compared the effectiveness and safety of the Biodesign anal fistula plug to the anorectal advancement flap in patients with transsphincteric anal fistulas. Methods: A total of 82 patients attending coloproctology clinics in Germany were enrolled in this prospective, non-blinded, multicenter trial and randomized to the advancement flap or the plug. Study endpoints included healing rates, health-related quality of life, continence-related quality of life, pain, and safety at the time of surgery and 2 weeks, 3, 6, and 12 months following surgery. Results: Follow-up at 12 months (n = 82) revealed healing rates of 67% for the plug and 76% for the flap (p = 0.56), with the noninferiority analysis confirming equivalence (p = 0.47). Fecal continence rates and the overall safety profile were similar between the two interventions. There were trends for lower pain scores at the time of surgery and 2 weeks postoperatively, and higher overall quality of life in the plug group. The surgical time required for the plug procedure was, on average, 34% shorter than the time required for the advancement flap. Regardless of treatment group, higher healing rates were observed in patients with a higher body mass index (p = 0.03), shorter fistula length (p = 0.01), and fewer previous colorectal surgeries (p < 0.001), while prior colorectal surgeries were associated with lower healing rates (p = 0.026). Conclusions: The plug and advancement flap were equally effective treatments for complex anorectal fistula, with the plug associated with significantly less surgical time and a favorable safety profile. (C) 2018 The Authors. Published by Elsevier Ltd on behalf of Surgical Associates Ltd.