[Fecal incontinence--anatomy/pathophysiology].

The ano-rectal organ derives from two different structures, the proctodaeum and the hindgut. The uro-rectal septum splits off the hindgut from the anterior part of the cloaca. This means that the anorectum has the same origin of nerves and blood vessels as the anterior part of the cloaca, which derives from the uro-genital sinus. In order to understand continence and defaecation, exact knowledge of the anatomy and physiology is compulsory. Studies in embryology are essential to the understanding of the anatomic and topographic structures.