The iliolumbar artery is the first branch of the posterior trunk of the
internal iliac artery. It turns upward behind the
obturator nerve and the
external iliac artery and vein, to the medial border of the
psoas major muscle, behind which it divides into: •
Lumbar branch of iliolumbar artery •
Iliac branch of iliolumbar artery Anastomoses • 1. Last lumbar→iliolumbar • 2. Lateral sacral↔lateral sacral • 3. Middle sacral→lateral sacral • 4. Superior hemorrhoidal→middle hemorrhoidal • 5. Medial femoral circumflex→inferior gluteal • 6. Medial femoral circumflex↔obturator • 7. Lateral femoral circumflex→superior gluteal • 8. Deep iliac circumflex→superior gluteal • 9. Deep iliac circumflex→external iliac • 10. Last lumbar→superior gluteal • 11. Last lumbar→deep iliac circumflex • 12. Iliolumbar→deep iliac circumflex. ==Additional images==