The lumbar arteries are
arteries
An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in ...
located in the lower back or
lumbar region
In tetrapod anatomy, lumbar is an adjective that means of or pertaining to the abdominal segment of the torso, between the diaphragm and the sacrum.
Naming and location
The lumbar region is sometimes referred to as the lower spine, or as an ...
. The lumbar arteries are in parallel with the
intercostals.
They are usually four in number on either side, and arise from the back of the
aorta
The aorta ( ; : aortas or aortae) is the main and largest artery in the human body, originating from the Ventricle (heart), left ventricle of the heart, branching upwards immediately after, and extending down to the abdomen, where it splits at ...
, opposite the bodies of the upper four
lumbar vertebrae
The lumbar vertebrae are located between the thoracic vertebrae and pelvis. They form the lower part of the back in humans, and the tail end of the back in quadrupeds. In humans, there are five lumbar vertebrae. The term is used to describe t ...
.
A fifth pair, small in size, is occasionally present: they arise from the
middle sacral artery.
They run lateralward and backward on the bodies of the
lumbar vertebrae
The lumbar vertebrae are located between the thoracic vertebrae and pelvis. They form the lower part of the back in humans, and the tail end of the back in quadrupeds. In humans, there are five lumbar vertebrae. The term is used to describe t ...
, behind the
sympathetic trunk
The sympathetic trunk (sympathetic chain, gangliated cord) is a paired bundle of nerve fibers that run from the base of the skull to the coccyx. It is a major component of the sympathetic nervous system.
Structure
The sympathetic trunk lies just ...
, to the intervals between the adjacent
transverse processes
Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spina ...
, and are then continued into the abdominal wall.
The arteries of the right side pass behind the
inferior vena cava
The inferior vena cava is a large vein that carries the deoxygenated blood from the lower and middle body into the right atrium of the heart. It is formed by the joining of the right and the left common iliac veins, usually at the level of the ...
, and the upper two on each side run behind the corresponding
crus of the
diaphragm.
The arteries of both sides pass beneath the
tendinous arches which give origin to the
psoas major
The psoas major ( or ; from ) is a long fusiform muscle located in the lateral lumbar region between the vertebral column and the brim of the lesser pelvis. It joins the iliacus muscle to form the iliopsoas. In other animals, this muscle is e ...
, and are then continued behind this muscle and the
lumbar plexus
The lumbar plexus is a web of nerves (a nerve plexus) in the lumbar region of the body which forms part of the larger lumbosacral plexus. It is formed by the divisions of the first four lumbar nerves (L1–L4) and from contributions of the su ...
.
They now cross the
quadratus lumborum
The quadratus lumborum muscle, informally called the ''QL'', is a paired muscle of the left and right posterior abdominal wall. It is the deepest abdominal muscle, and commonly referred to as a back muscle. Each muscle of the pair is an irregular ...
, the upper three arteries running behind, the last usually in front of the muscle.
At the lateral border of the quadratus lumborum they pierce the posterior aponeurosis of the
transversus abdominis and are carried forward between this muscle and the
obliquus internus.
They anastomose with the
lower intercostal, the
subcostal, the
iliolumbar, the
deep iliac circumflex, and the
inferior epigastric arteries.
Additional images
Image:Gray1120.png, The relations of the viscera and large vessels of the abdomen.
See also
*
Lumbar veins
References
*
External links
* - "Branches of the Abdominal Aorta"
* - "The Abdominal Aorta"
* - "Parietal and visceral branches of the abdominal aorta."
{{Authority control
Arteries of the abdomen