The subcostal nerve (anterior division of the twelfth thoracic nerve
) is a mixed motor and sensory nerve contributing to 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 ...
. It runs along the lower border of the
twelfth rib
The rib cage or thoracic cage is an endoskeletal enclosure in the thorax of most vertebrates that comprises the ribs, vertebral column and sternum, which protect the vital organs of the thoracic cavity, such as the heart, lungs and great vessel ...
, often gives a communicating branch to the first
lumbar nerve
The lumbar nerves are the five pairs of spinal nerves emerging from the lumbar vertebrae. They are divided into posterior and anterior divisions.
Structure
The lumbar nerves are five spinal nerves which arise from either side of the spinal cord ...
, and passes under the
lateral lumbocostal arch.
It then runs in front of 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 ...
, innervates the
transversus, and passes forward between it and the
abdominal internal oblique to be distributed in the same manner as the
lower intercostal nerves.
It communicates with the
iliohypogastric nerve
The iliohypogastric nerve is a nerve that originates from the lumbar plexus that supplies sensation to skin over the lateral gluteal and hypogastric regions and motor to the internal oblique muscles and transverse abdominal muscles.
Structur ...
and the
ilioinguinal nerve
The ilioinguinal nerve is a branch of the first lumbar nerve (L1). It separates from the first lumbar nerve along with the larger iliohypogastric nerve. It emerges from the lateral border of the psoas major just inferior to the iliohypogastric, ...
of 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 ...
,
and gives a branch to the
pyramidalis muscle
The pyramidalis muscle is a small triangular muscle, anterior to the rectus abdominis muscle, and contained in the rectus sheath.
Structure
The pyramidalis muscle is part of the anterior abdominal wall. Inferiorly, the pyramidalis muscle attache ...
and the
quadratus lumborum muscle
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 ...
.
It also gives off a lateral cutaneous branch that supplies sensory innervation to the skin over the hip.
Additional images
File:Nervous system diagram-en.svg, Nervous system
File:Gray803.png, The posterior divisions of the sacral nerves.
File:Gray822.png, Plan of lumbar plexus.
File:Gray825and830.PNG, Cutaneous nerves of the right lower extremity. Front and posterior views.
See also
*
Subcostal artery
The subcostal arteries, so named because they lie below the last ribs, constitute the lowest pair of branches derived from the thoracic aorta, and are in series with the intercostal arteries.
Anatomy
Course and relations
Each intercostal art ...
*
Subcostal vein
The subcostal vein is a vein in the human body that runs along the bottom of the twelfth rib. It has the same essential qualities as the posterior intercostal veins, except that it cannot be considered ''intercostal'' because it is not between t ...
References
External links
* ()
*
* - "Posterior Abdominal Wall, Dissection, Anterior View"
* - "Muscles and nerves of the posterior abdominal wall."
*
Spinal nerves
{{Neuroanatomy-stub