The role of dilatation methods and lateral subcutaneous sphincterotomy in the internal anal sphincter spasm treatment (systematic literature review and meta-analysis)

The main link in the pathogenesis of anal fissure is a spasm of the internal sphincter of the rectum, in connection with which many methods of muscle relaxation have been developed. A special place is occupied by dilatation methods, which are quite diverse. To assess their effectiveness and safety, the authors carried out a systematic review and meta-analysis of 9 selected randomized clinical trials comparing the results of treatment of chronic anal fissure using dilatation methods of internal anal sphincter relaxation and the traditionally used method of lateral subcutaneous sphincterotomy. The results of treatment of 716 patients were analyzed with an assessment of such indicators as the frequency of fissures epithelialization, postoperative complications, and the development of anal sphincter insufficiency and relapses of the disease. There were no statistically significant differences in the frequency of fissure healing in the groups with the use of dilatation methods of internal sphincter relaxation and lateral subcutaneous sphincterotomy (OR=1; CI=0.34;2.96; p=1). When assessing the risk of the disease recurrence in both groups, there were also no statistically significant differences (OR=0.93; CI=0.56;1.56; p=0.79). Postoperative complications were also comparable in both groups (OR=0.81; CI=0.4;1.63; p=0.55). There were no statistically significant differences in the incidence of anal incontinence (OR=1; CI=0.34;2.96; p=1). It should be noted that the use of uncontrolled dilatation is associated with a high risk of developing anal incontinence, while the introduction of controlled dilatation reduces the risk of this complication to a minimum. The use of controlled dilatation methods for relaxation of the internal sphincter is a safe alternative to lateral subcutaneous sphincterotomy, including in the treatment of anal fissures in combination with hemorrhoids.