Long-term efficacy and safety of a nitinol closure clip system for anal fistula treatment

Introduction: Treatment failure of anal fistula results in high re-occurrence rate. Material and methods: Efficacy and safety of a nitinol closure clip system (bear-claw clip) were evaluated for anal fistulae treatment in a 36-month long-term follow-up study. Results: Twenty-two patients were included. No patient had been treated with a bear-claw clip system before. All patients were fully continent before treatment. Follow-up time was 36 months (range 19-48 months). We observed a re-occurrence rate of 41% (nine patients) with presence of an active fistula. Time to recurrence was on average 6.9 months (range 3-11 months). Thirteen patients (59%) showed a complete healing of the fistula. Placed clip was removed in all patients on average after almost 5.8 months (3-12 months), in three cases the clip was left in situ. We did not observe any incontinence; one patient reported recurrent burning after defecation once the clip system was removed. Discussions: Clip placement is a minimally invasive sphincter-preserving procedure with minimal complications and with an acceptable recurrence rate in the long term. However, bear-claw clip placement should probably be offered patients as a treatment option before more invasive procedures with higher perioperative morbidity are taken into consideration.