Comparison of porcine collagen paste injection and rectal advancement flap for the treatment of complex cryptoglandular anal fistulas: a 2-year follow-up study.

Background: Rectal advancement flap is the standard surgical treatment for complex cryptoglandular anal fistulas, while Permacol™ collagen paste is considered an innovative treatment option for anorectal fistulas. This study aimed to compare the clinical outcomes of patients with complex cryptoglandular fistulas treated by endorectal advancement flap versus Permacol™ paste.

Methods: This study was a retrospective analysis of patients with complex cryptoglandular anal fistulas. Thirty-one patients were treated with the rectal advancement flap (RAF group), while 21 were treated with Permacol™ paste injection (PP group). In PP group, the approach consisted of loose seton positioning followed several weeks later by closure internal opening with a resorbable sutures associated with paste injection into the fistula track. Clinical outcomes were assessed in terms of healing rate, faecal continence and patient satisfaction.

Results: Seton drainage was done in all patients in both groups for a median duration of 8 weeks (range 4-18 weeks) before the final surgery (p = 0.719). No patient had faecal incontinence (CGS ≥ 5) preoperatively. Five patients (16%) in the RAF group and one (5%) in the PP group experienced faecal incontinence postoperatively. The 2-year disease-free survival was 65% in the RAF group and 52% in the PP group (p = 0.659). The median satisfaction scores were 5 (range 1-10) in the RAF group and 7 (range 2-10) in the PP group (p = 0.299).

Conclusion: The RAF appeared superior to PP in terms of fistula healing, although this result was not statistically significant. On the contrary, PP has a potential advantage in terms of continence disorders. Permacol™ paste can be considered as the initial treatment option for complex cryptoglandular anal fistulas in patients with faecal continence disorders.