Comparison of skin incisions used for open lateral internal sphincterotomies – Radial versus circumferential incisions: A retrospective cohort study

•Lateral internal sphincterotomy (LIS) is a popular surgical treatment for fissure-in-ano.•Radial or circumferential incisions are used for LIS, based on the surgeons' preference.•We compared the two types of incisions used during LIS.•Circumferential skin incisions are associated with shorter healing times than radial incisions.

Introduction: Lateral internal sphincterotomy (LIS) is a safe and effective surgical treatment, commonly used in patients with chronic anal fissures (CAFs). Although LIS is a simple surgical technique, it may cause several complications. Open LIS is usually performed through an incision made in the intersphincteric groove; radial or circumferential incisions, used according to the surgeon's preference. However, differences in clinical outcomes and wound healing, based on type of skin incision, are unclear. We investigated incision site wound healing and other clinical outcomes, after open LIS, according to the type of skin incision employed. Methods: We retrospectively reviewed the data of the electronic medical records of 602 patients who underwent open LIS for CAFs between March 2005 and February 2010 at Yang Hospital, Seoul, Korea. Results: Of the 602 patients, 298 patients received radial incisions and 304 received circumferential incisions. Circumferential incisions of the anus reduced the wound healing time compared to radial incisions (19.1 vs. 24.0 days, p < 0.001). There were no significant differences between the groups in wound complications such as perianal abscess, fistula, or cellulitis. Clinical outcomes including recurrence, persistence of fissures, and continence problems were also similar between the groups. Conclusions: Our study shows that circumferential skin incisions, during LIS, are associated with shorter healing times than radial incisions.