In a consecutive series of 46 possible candidates for total colectomy, mucosal proctectomy, and ileal reservoir to an anal anastomosis, we have compared the clinical outcome of group I, with a long efferent leg (12 cm), and group II, with a short efferent leg (3-5 cm). The surgical procedure was done in three steps: first, a total colectomy; second, mucosal proctectomy and construction of an 'S-shaped' ileal reservoir with a temporary loop ileostomy; and, third, closing of the ileostomy. Nine patients with a long efferent leg and eight patients with a short leg were observed for 2-51 months with a functioning ileal reservoir. The overall mortality was zero. The results showed that the short efferent leg was important for low fecal urgency, spontaneous evacuation of stools, minimal soiling, independence of reservoir catheterization, and use of antidiarrheal drugs. The length of the efferent leg did not influence the function of the anal sphincter itself. The postoperative sexual life was unchanged, and all patients in group II had a better resocialization than those in group I. The selection of candidates for ileal reservoir operations from among patients with ulcerative colitis or familiar polyposis is most important because of a relatively long postoperative course and high incidence of surgical complications. more...