The iliolumbar artery is one of three branches of the posterior division of the internal iliac artery.
- origin: posterior division of the internal iliac artery
- location: pelvis
- supply: ilium, iliacus muscle, psoas major muscle, quadratus lumborum muscle, erector spinae muscle, anterior superior iliac spine anastomoses and the L5/S1 foramen
- branches: iliac and lumbar branches
Origin and branches
The iliolumbar artery originates from the posterior division of the internal iliac artery. It proceeds posteriorly and superolaterally toward the iliac fossa. Here it divides into iliac and lumbar branches.
The iliac branch supplies the iliac fossa. The lumbar branch proceeds laterally towards muscles of the posterior abdominal wall, which it subsequently supplies.
The iliac branch of the iliolumbar artery supplies the ilium and iliacus muscle as well as contributing to anastomoses around the anterior superior iliac spine.
The lumbar branch supplies the foramen between L5 and S1. It proceeds towards psoas major and quadratus lumborum, which it also supplies. It extends posteriorly and also gives supply to the erector spinae.
The iliolumbar artery is often quoted as the first branch of the posterior division of the internal iliac artery, however the order may vary. It may arise directly from the internal iliac artery, the common iliac artery, or other branches of the internal iliac artery.
The iliolumbar artery may be injured in trauma of the sacrum, lumbar spine or pelvis.