Rectum

Synonyms

Distal part of the large intestine; The pelvic part of the alimentary tract

Anatomy (Macroscopy)

Begins at the rectosigmoid junction- at the level of third sacral vertebra and ends at the anorectal junction- 2–3 cm in front of and a little below the coccyx. The median sacral vessels and the roots of the sacral nerve plexus lie posterior to the rectum. Anteriorly; in women, the rectum is closely related to the uterine cervix and posterior vaginal wall, in men, it lies behind the bladder, vas deferens, seminal vesicles, and prostate. The non-mobilized rectum has three lateral curves: the upper and the lower are convex to the right and the middle is convex to the left. These curves correspond intraluminally to the folds or valves of Houston (Fig. 1). The middle valve is the most consistent in presence and location (also known as Kohlrausch’s plica) and corresponds to the level of the anterior peritoneal reflection. The rectum is characterized by the absence of taeniae, epiploic...