The iliac fossa is bounded above by the
iliac crest, and below by the
arcuate line. It is bordered in front and behind by the anterior and posterior borders of the
ilium. The iliac fossa gives origin to the
iliacus muscle. The
obturator nerve passes around the iliac fossa. It is perforated at its inner part by a
nutrient canal. Below it there is a smooth, rounded border, the
arcuate line, which runs anterior, inferior, and medial. When the "left" or "right" adjective is used (e.g. "right iliac fossa"), the iliac fossa usually means one of the
inguinal regions of the
nine regions of the
abdomen. ==Additional images==