326 The Large Intestine 



to the right sacro-iliac synchondrosis. It is spread out like a fan, 

 and its intestinal border is about 20 ft. long. The measurement from 

 the spinal to the intestinal border is 4 or 6 in., and the question still 

 remains unanswered if, in a hernia, the mesentery was so deep as to 

 let the bowel slip into the inguinal or femoral canal, or if the fold was 

 pulled down and elongated by the emigrant bowel. The lymphatic 

 -lands at the root of the mesentery are prone to tubercular inflamma- 

 tion ; the disease may spread and glue together adjacent coils of 

 intestine, or may determine a suppurative peritonitis. 



After resecting a piece of small intestine the edges of the tri- 

 angular gap in the mesentery must be carefully adjusted by sutures. 



The end of the ileum, especially in children, is apt to slip through 

 the ileo-caecal valve, and, with the invaginated caecum, to be carried 

 along the colon and possibly through the anus. In a few happy cases 

 of this sort the invaginated bowel has sloughed off and the patient 

 recovered. 



Forcible inflation of the lower bowel occasionally succeeds in un- 

 sheathing the piece when the adjacent serous surfaces have not become 

 too closely adherent by plastic effusion ; abdominal section, too, has 

 in rare instances availed (* Lancet,' August 4, 1888). Opium is the only 

 drug to be prescribed : absolute quiet is essential. 



The colon, about 5 ft., ascends from the right iliac fossa through 

 the right lumbar into the hypochondriac region, passing in front of 

 the quadratus lumborum, kidney, and descending piece of duodenum 

 to the right lobe of the liver. Thence it turns across the top of the 

 umbilical region below the stomach ; reaching the spleen well behind 

 the stomach, it descends in front of the left kidney and quadratus, and, 

 at the end of the sigmoid flexure, is continued on as the rectum. 

 As it passes across the abdomen it lies over the vertebral column and 

 the large vessels ; aortic abdominal aneurysm is apt to burst into the 

 transverse colon. The transverse colon is often found in the sac of an 

 umbilical hernia. Gall-stones may escape into the hepatic flexure, and 

 renal or spinal abscess may be evacuated through the ascending or 

 descending parts. 



The sigmoid flexure is apt, in habitual constipation, to be so laden 

 with faeces as to form a doughy tumour in the left iliac fossa. Some- 

 times a sigmoid loop swings over, producing that form of obstruction 

 known as volvulus. With obstruction so low in the bowel the abdo- 

 minal distension is extreme. In obstruction of the rectum the sigmoid 

 flexure may become an enormous faecal reservoir which occupies the 

 chief part of the abdominal cavity. 



The ascending and descending colon are not generally entirely 

 invested with peritoneum ; the postero-internal strip is likely to be 

 bare, and it is through that part that the bowel is opened in lumbar 

 colotomy, as is shown on the next page. 



The caecum, which as a rule is entirely surrounded by peritoneum, 



