[Sphincter function and continence after 2/3-division of the sphincter ani internus].

Pressure and motility in the anal canal in 24 patients with various benign anal disorders were measured before and 4-8 months after partial sphincterotomy. The clinical results were good in most cases. Postoperative manometric measurements showed a drop in pressure and an abolition of irregular slow waves. Partial sphincterotomy is a rational treatment because it corrects a pathological activity of the internal sphincter.