PURPOSE:A prospective defecographic study was performed to evaluate the anorectal physiology of dynamic graciloplasty (gracilis muscle transposition and subsequent implantation of an electric stimulator) for treatment of fecal incontinence.METHODS:From November 1986 until May 1993, 38 consecutive patients with incapacitating fecal incontinence were treated with “anal dynamic graciloplasty.” Defecography was performed before and after surgical procedures. Defecographic data (anorectal angle, perineal descent, anal canal length, anal canal width, and anal leakage) were correlated with respect to clinical outcome and anal manometry.RESULTS:Fecal continence was achieved in 24 patients, which correlated significantly with no leakage of barium contrast during defecography(P<0.01, Kruskal‐Wallis one‐way analysis of variance). In addition, minimum anal canal width decreased from 7 mm before surgery to 1 mm after dynamic graciloplasty(P<0.01, paired Student'st‐test).CONCLUSION:Defecography is an efficient method to evaluate dynamic graciloplasty for fecal incontinence.