Diverticulosis and Diverticulitis Diverticulosis is a condition
in which the inner layer of the colon herniates (bulges out)
through the outer, muscular layer, creating pouches called
diverticula. Diverticulitis refers to inflammation and infection
in one or more diverticula. Diverticula tend to occur most
frequently in the last segment of the large intestine, the
sigmoid colon. They occur with decreasing frequency toward the
beginning of the colon. The chance of developing diverticula
increases with age, so that by the age of 50, about 20–50% of
all people will have some diverticula. By the age of 90,
virtually everyone will have developed some diverticula. Most
diverticula measure about 3 mm (0.19 inches) to just over 3 cm
(1.18 inches) in diameter. Larger, or giant diverticula, are
extremely rare, but may measure as large as 15 cm (5.9 inches)
in diameter. Causes and symptoms Diverticula are believed to be
caused by overly forceful contractions of the muscular wall of
the large intestine, often caused by s