Common iliac artery


The common iliac arteries are two large arteries that originate from the aortic bifurcation at the level of the fourth lumbar vertebra. They end in front of the sacroiliac joint, one on either side, and each bifurcates into the external and internal iliac arteries.
They are about 4 cm long in adults and more than a centimeter in diameter. The arteries run inferolaterally, along the medial border of the psoas muscles to their bifurcation at the pelvic brim, in front of the sacroiliac joints.
The common iliac artery, and all of its branches, exist as paired structures.
The distribution of the common iliac artery is basically the pelvis and lower limb on the corresponding side.

Relations

Both common iliac arteries are accompanied along their course by the two common iliac veins which lie posteriorly and to the right. Their terminal bifurcation is crossed anteriorly by the ureters. This is significant as the bifurcation of the common iliac artery is the second point of ureteric constriction.

Dilatation

Dilatation of the common iliac artery can be graded into the following categories:
NormalDiameter ≤12 mm
EctasiaDiameter 12 to 18 mm
AneurysmDiameter ≥18 mm

Additional images