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, often gives a communicating branch to the first
lumbar nerve, and passes under the
lateral lumbocostal arch.
It then runs in front of the
quadratus lumborum, 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 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.
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
*
Subcostal vein
References
External links
* ()
*
* - "Posterior Abdominal Wall, Dissection, Anterior View"
* - "Muscles and nerves of the posterior abdominal wall."
*
Spinal nerves
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