Anatomy of the rectum and anal canal.

The rectum and anal canal are the terminal portions of large intestine and the entire gastrointestinal tract. They are thus readily accessible to direct inspection and examination. The rectum functions as a distensible reservoir for faeces, while the anal canal possesses a powerful muscular sphincter in its wall which is important in maintaining faecal continence. Diseases of the rectum and anal canal, both benign and malignant, account for a very large part of colorectal surgical practice worldwide. This article emphasizes the clinically and surgically relevant aspects of the anatomy of the rectum and anal canal. [ABSTRACT FROM AUTHOR]