APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -The adult human rectum is about 12 centimetres (4.7 in) long, and begins at the rectosigmoid junction (the end of the sigmoid colon) at the level of the third sacral vertebra or the sacral promontory depending upon what definition is used.

Detailed explanation-2: -Abstract. Aim: The rectosigmoid junction is the limit separating the sigmoid colon and rectum.

Detailed explanation-3: -The anatomical, histological, and radiological findings thus indicate that the RSJ is a segment which can be identified by its interior rather than outer aspect. The study suggests the presence of an anatomical sphincter at the RSJ which seems to regulate the passage of stools from the sigmoid colon to the rectum.

Detailed explanation-4: -The sigmoid colon is an “S” shaped portion of the large intestine that begins in front of the pelvic brim as a continuation of the descending colon and becomes the rectum at the level of the third sacral vertebrae.