Arteria lumbalis
The lumbar arteries are paired branches of the abdominal aorta arising in the lumbar region.
Gross anatomy
Origin
There are most commonly four paired lumbar arteries originating as posterolateral branches of the abdominal aorta on either side, at the level of L1-4.
Course
The paired arteries course posterolaterally along the vertebral bodies, the right-sided arteries posterior to the inferior vena cava (IVC), then pass under the tendinous arches of psoas major and sympathetic trunks. After crossing quadratus lumborum, the arteries enter the space between the transversus abdominis and internal oblique muscles. There are anastomoses with the lower intercostal, subcostal, iliolumbar, deep circumflex iliac, inferior epigastric and contralateral lumbar arteries.
Branches
Dorsal branches, which give rise to the spinal branches that enter the vertebral canal.
Supply
Dorsal muscles of the back, fascia, ligaments, vertebrae and intervertebral discs.
Variant anatomy
A smaller fifth pair of lumbar arteries may be present, arising from the median sacral artery. The lumbar arteries may arise from a common trunk.