The Position of the Large Intestine in Infants and its Relation to Constipation

Abstract

The work presented in this paper was undertaken, first, to ascertain the differences in shape and position of the large intestine in infants, especially of the iliac and sigmoid colons; and, secondly, to see if there is any real relation between any of these types and constipation in infants.Anatomy.-A short account of the anatomical characters of the descending colon, iliac and sigmoid portions of the large intestine in adults will help much to the appreciation of the differences we came across in these portions of the large intestine in infants.The descending colon passes downwards through the left hypochondriac and lumbar regions and in front of the lower part of the left kidney. At the lower end of the kidney, it turns medially towards the lateral border of the psoas major, and descends in the angle between the psoas major and quadratus lumborum muscles to the crest of the ilium; it then curves downwards and medially in front of the iliacus and psoas major, and ends in the sigmoid colon at the superior aperture of the lesser pelvis. That portion of the descending colon which extends from the ilium to the superior aperture of the lesser pelvis is sometimes named the iliac colon.The sigmoid colon, sometimes called the pelvic colon, begins at the superior aperture of the lesser pelvis where it is continuous with the descending colon; it forms a loop which averages about 20 cm. in length and normally lies within the pelvis. The loop consists of three parts. The first part descends in contact with the left pelvic wall; the second crosses the pelvic cavity between the rectum and bladder in the male, and the rectum and uterus in the female, and may come in contact with the right pelvic wall; the third arches backwards and reaches the mid-line at the level of the third piece of the sacrum where it bends downwards and ends in the rectum.The position and shape of the sigmoid colon vary very much and depend on:-(1) Its length.(2) The length and freedom of its mesocolon.

Elongation and Dilatation of Colon

“…From consideration of this clinical grouping it is quite clear that anatomical abnormalities of the colon do not inevitably cause constipation, and the success of a simple regime in cases showing elongation and/or dilatation seems to me to provide weighty evidence against the possibility of such anatomical conditions ever directly causing constipation. This view is supported by the observations of Khalik,Erfan, and Askar (1932),who found that anatomical variations in the length and calibre of the colon were common in infants who did not suffer from constipation. In the presence of faecal stasis it is conceivable that the pbssession of a long colon may increase and tend to perpetuate the condition by so altering the alignment of the large bowel-that the massive ontward nmovenment of its contenits preliminary to defaecation is impeded.…”