ABSTRACT
This chapter discusses a number of important colorectal conditions that have not been covered previously: colonic volvulus, ischemic colitis, radiation bowel injuries, and colorectal trauma.
COLONIC VOLVULUS
Volvulus is the axial torsion or twisting of the bowel on its mesentery to a degree sufficient to cause symptoms [1]. Symptoms result from the partial or complete obstruction of the lumen and associated vascular compromise. If the volvulus is not reduced, the circulatory impairment and increased interluminal pressure may lead to gangrene and perforation. The incidence of large bowel obstruction from chronic volvulus varies worldwide. In the United States, Ballantyne [2] found that chronic volvulus accounted for 3.4% of intestinal obstructions and 9.6% of chronic obstructions. Certain populations in Africa, Western Europe, and Iran have reported an increased frequency of volvulus. This increased frequency is felt to result from a long, redundant colon acquired because of the presence of
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a high degree of coarse vegetable fiber in the diet (see below). The incidence of volvulus in these areas averages 20-30%, with highs of 85% in northern Iran and 54.2% in Ethiopia [3]. The distribution of chronic volvulus is 80% in the sigmoid colon, 15% in the cecum, 3% in the transverse colon, and 2% in the splenic flecture [4]. Each type of volvulus will be discussed in detail.
