Studies of manometric abnormalities of the rectoanal region during defecation in constipated and soiling children: modification through biofeedback therapy.Am J Gastroenterol. 1988 Aug; 83(8):827-31.AJ
Anorectal manometry was performed on 12 normal children and 18 patients suffering from constipation and soiling. In both groups, the results of the rectoanal inhibitory reflex and the squeezing anal pressure were similar. The pressure recording in all the normal children showed that the anal canal relaxed during defecation. Fourteen (78%) constipated children closed the anal canal while straining by contracting the anal sphincter. This paradoxical contraction appears to be the cause of chronic constipation. Twelve children with paradoxical anal closure were treated by biofeedback therapy. The results show that all these children were successfully conditioned to relax their anal sphincter during defecation. This therapy improved their bowel habits and relieved them from constipation and soiling. It is proposed that the paradoxical anal closure itself is the result of a self-conditioning process. In this process, the patient learns to paradoxically contract the external anal sphincter in response to the urge and the act of defecation. Biofeedback therapy seems to be the appropriate treatment in such cases.