Functional constipation: results of application of the colorectal laboratory.

Constipation and defaecation may be considered as the last taboo. The inability of defaecate or to achieve this only by digital evacuation has never been a popular topic among patients and doctors. Application of tests from the colorectal laboratory has made it possible to study the function of the different parts of the colon and the mechanism of continence. Two types of constipation can be distinguished: I slow transit, which is probably a systemic disease, and 2 functional colonic outlet obstruction due to abnormal pelvic floor function during defaecation straining, which is likely to be a behavioural disorder. Since 30 per cent of the patients with constipation have a normal total colonic transit time, constipation is not merely related to a low frequency of defaecation, but should be defined as a difficult and painful rectal evacuation which may even be impossible over several days.