The sigmoid colon is the lower part of the large intestine and a flexible sigmoidoscopy is performed to view the sigmoid colon. This examination investigates the rectal lining and the lower part of the colon. A flexible tube with a camera is inserted into the rectum and guided up to the sigmoid colon. In contrast to colonoscopy, a sigmoidoscopy only examines the lower one third of the colon. This procedure is performed to determine cause of abdominal pain, diarrhea or constipation intestinal bleeding, inflammation, abnormal growths and ulcers. The procedure usually lasts about 15 minutes and recovery takes another 20 minutes.