The anterior abdominal wall

Abstract Anteriorly, in the midline, the abdominal wall extends from the surface of the xiphoid process to the pubic symphysis. On each side, the wall extends from the costal margin to the inguinal ligament. For purposes of description, the anterior abdominal wall is divided into nine regions by two vertical and two horizontal planes. The right and left vertical planes pass through the mid-inguinal points—a point on each inguinal ligament midway between the anterior superior iliac spine and the pubic symphysis. The transpyloric plane lies horizontally midway between the jugular notch of the sternum and the pubic symphysis, approximately midway between the xiphoid process and the umbilicus. It lies at the level of the first lumbar vertebra. The transtubercular plane passes horizontally through the tubercles of the iliac crests at the level of the fifth lumbar vertebra. The nine regions demarcated by these planes: are: (1) epigastric; (2 and 3) right and left hypochondrium; (4) umbilical or central; (5 and 6) right and left lumbar; (7) hypogastric or suprapubic; and (8 and 9) right and left iliac fossae. Common surgical incisions used in opening the abdomen are described.