Ventral ramus
Encyclopedia
The ventral ramus
(anterior ramus, anterior branch, anterior divisions of the spinal nerves) supply the antero-lateral parts of the trunk, and the limbs; they are for the most part larger than the posterior divisions.
In the thoracic region they remain distinct from each other and each innervates a narrow
strip of muscle and skin along the sides, chest, ribs, and abdominal wall. These rami are called the
intercostal nerves
. In regions other than the thoracic, ventral rami converge with each other to form networks of nerves
called nerve plexuses. Within each plexus, fibers from the various ventral rami branch and
become redistributed so that each nerve exiting the plexus has fibers from several different spinal
nerves. One advantage to having plexuses is that damage to a single spinal nerve will not completely
paralyze a limb.
There are four main plexuses formed by the ventral rami:
The cervical plexus
contains ventral rami from spinal nerves C1-C5. Branches of the
cervical plexus, which include the phrenic nerve, innervate muscles of the neck, the diaphragm, and the
skin of the neck and upper chest.
The brachial plexus
contains ventral rami from spinal nerves C5-T1. This plexus innervates
the pectoral girdle and upper limb.
The lumbar plexus contains ventral rami from spinal nerves L1-L4. The sacral plexus
contains ventral
rami from spinal nerves L4-S4. The lumbar and sacral plexuses innervate the pelvic girdle and lower
limbs.
The Ventral rami, including the sinuvertebral nerve branches, supply structures anterior to the facet joint, including the vertebral bodies, the discs and their ligaments, and joins other spinal nerves to form the lumbo-sacral plexus.
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Ventral ramus
The ventral ramus supply the antero-lateral parts of the trunk, and the limbs; they are for the most part larger than the posterior divisions....
(anterior ramus, anterior branch, anterior divisions of the spinal nerves) supply the antero-lateral parts of the trunk, and the limbs; they are for the most part larger than the posterior divisions.
In the thoracic region they remain distinct from each other and each innervates a narrow
strip of muscle and skin along the sides, chest, ribs, and abdominal wall. These rami are called the
intercostal nerves
Intercostal nerves
The intercostal nerves are the anterior divisions of the thoracic spinal nerves from T1 to T11.Each nerve is connected with the adjoining ganglion of the sympathetic trunk by a gray and a white ramus communicans...
. In regions other than the thoracic, ventral rami converge with each other to form networks of nerves
called nerve plexuses. Within each plexus, fibers from the various ventral rami branch and
become redistributed so that each nerve exiting the plexus has fibers from several different spinal
nerves. One advantage to having plexuses is that damage to a single spinal nerve will not completely
paralyze a limb.
There are four main plexuses formed by the ventral rami:
The cervical plexus
Cervical plexus
The cervical plexus is a plexus of the ventral rami of the first four cervical spinal nerves which are located from C1 to C4 cervical segment in the neck. They are located laterally to the transverse processes between prevertebral muscles from the medial side and vertebral from lateral side...
contains ventral rami from spinal nerves C1-C5. Branches of the
cervical plexus, which include the phrenic nerve, innervate muscles of the neck, the diaphragm, and the
skin of the neck and upper chest.
The brachial plexus
Brachial plexus
The brachial plexus is a network of nerve fibers, running from the spine, formed by the ventral rami of the lower four cervical and first thoracic nerve roots...
contains ventral rami from spinal nerves C5-T1. This plexus innervates
the pectoral girdle and upper limb.
The lumbar plexus contains ventral rami from spinal nerves L1-L4. The sacral plexus
Sacral plexus
-External links:*...
contains ventral
rami from spinal nerves L4-S4. The lumbar and sacral plexuses innervate the pelvic girdle and lower
limbs.
The Ventral rami, including the sinuvertebral nerve branches, supply structures anterior to the facet joint, including the vertebral bodies, the discs and their ligaments, and joins other spinal nerves to form the lumbo-sacral plexus.
External links
- "Lumbosacral plexusLumbosacral plexus
The anterior divisions of the lumbar nerves, sacral nerves, and coccygeal nerve form the lumbosacral plexus, the first lumbar nerve being frequently joined by a branch from the twelfth thoracic. For descriptive purposes this plexus is usually divided into three parts:* lumbar plexus* sacral plexus*...
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