Continence organ

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The continence organ , also known as the closing device , is the closing device of the anus . The functioning continence organ ensures continence . Illnesses, malformations or injuries to the continence organ can lead to fecal incontinence . The person concerned is then no longer in a position to arbitrarily hold back his stool or wind .

Anatomy and function

Schematic representation of the continence organ of a healthy person with an open sphincter muscle

The continence organ is composed of several anatomical structures. The correct function and interaction of the individual components is of great importance for continence. The main components are the rectum , the muscles, the corpus cavernosum recti (hemorrhoidal cushion), the anoderm and the associated nervous system.

For the coarse final a funnel-shaped structure of the muscular from the musculature of the used pelvic floor ( puborectalis muscle and levator ani muscle ) and the inner ( internal anal sphincter ) and outer ( musculus sphincter ani externus ) sphincter is formed. The internal sphincter has a ring-shaped structure made up of smooth muscles . This autonomic muscle only relaxes during defecation. It provides the largest share of the continence service. When the ampulla recti in the rectum is filled, the internal anus muscle relaxes , allowing intestinal contents to reach the highly sensitive anoderm (anal mucous membrane). The anoderm, which is interspersed with many nerve endings, is able to differentiate between intestinal gases, liquids and solids. The external sphincter, which belongs to the striated muscles , supports the closure of the anal canal when at rest. It can be consciously contracted vigorously, for example when there is a strong need to defecate, whereby the intestinal contents are pushed out of the anal canal back into the ampulla recti . This means that bowel movements can be deliberately suppressed ("pinch pressure"), even when the ampoule is full and there is strong defecation stimulus.

The sphincter muscles of the anus are not able to close the anal canal on their own. Even with a maximum contraction of these spinal muscles, an opening about 10 mm in diameter would remain, which can only be closed by the canalis ani muscle and the corpus cavernosum recti (hemorrhoidal plexus) sitting on it. If the internal sphincter is tense, the venous outflow is restricted and the hemorrhoidal plexus fills with blood. This prevents the passage of feces and intestinal gases . The hemorrhoidal plexus is of great importance for fine continence.

Diseases of the continence organ

A number of diseases can affect the continence organ and consequently limit continence or lead to fecal incontinence. These include rectal cancer , hemorrhoids , anal fistulas and abscesses .

further reading

  • A. Winkelmann, J. Kirsch and others: Pocket textbook anatomy. Georg Thieme Verlag, 2010, ISBN 3-131-62511-2 , p. 386. Restricted preview in the Google book search
  • T. Wedel: Functional anatomy - a prerequisite for understanding defecation disorders. In: Chir Gastroenterol. Volume 23, Number 3, 2007, pp. 220-227. doi : 10.1159 / 000105168

Individual evidence

  1. ↑ S. Unterkirchner, P. Fritsch: Proktologie. In: P. Fritsch: Dermatology, Venereology. Gabler Wissenschaftsverlage, 2004, ISBN 3-540-00332-0 , p. 808. Restricted preview in Google book search
  2. ↑ H. Bünte, K. Bünte: The spectrum of medicine. Schattauer Verlag, 2004, ISBN 3-794-52374-1 , p. 780. Restricted preview in Google book search
  3. ↑ H. Stieve : About the importance of venous miracle nets for the closure of individual openings in the human body. In: German Medical Weekly . Volume 54, Number 3, 1928, pp. 87-90, doi : 10.1055 / s-0028-1124946 .
  4. ↑ HH Hansen: The importance of the canalis ani muscle for continence and anorectal diseases. In: Langenbecks Arch Chir. Volume 341, Number 1, June 1976, pp. 23-37, ISSN  0023-8236 . PMID 957838 .
  5. ↑ G. Pühse, F. Raulf: Das Hämorrhoidalleiden. In: Urologe A. Volume 46, Number 3, March 2007, pp. W303-W314, ISSN  0340-2592 . doi : 10.1007 / s00120-006-1281-6 . PMID 17294153 . (Review).