spinal nerves


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spi·nal nerves

[TA]
the nerves emerging from the spinal cord; there are 31 pairs, each arising from the cord by rootlets that converge to form two roots, anterior (ventral or motor) and posterior (dorsal or sensory); the latter type is provided with a circumscribed enlargement, the spinal (dorsal root) ganglion; the two roots unite in the intervertebral foramen, and the mixed spinal nerve almost immediately divides again into anterior and posterior (primary) rami, the former supplying the anterolateral trunk and the limbs, the latter the true muscles and overlying skin of the back.
Synonym(s): nervi spinales [TA]

spinal nerves

the 31 pairs of nerves without special names that are connected to the spinal cord and numbered according to the level of the vertebral column at which they emerge. There are 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal pair. The first cervical pair of nerves emerges from the spinal cord in the space between the first cervical vertebra and the occipital bone. The rest of the cervical pairs and all the thoracic pairs emerge horizontally through the intervertebral foramina of their respective vertebrae, such as the second cervical pair, which emerges through the foramina above the second cervical vertebra. The lumbar, sacral, and coccygeal nerve pairs descend from their points of origin at the lower end of the cord before reaching the intervertebral foramina of their respective vertebrae. Each spinal nerve attaches to the spinal cord by an anterior (or ventral) root and a posterior (or dorsal) root. The nerve impulses enter the cord by way of posterior roots. The posterior roots supply skin and muscles of much of the body with some of the nerve fibers supplying autonomic functions. The posterior roots contain sensory neurons and accompany a distended spinal ganglion within the vertebral foramina. The ventral roots contain motor neuron axons. The sacral plexus in the pelvic cavity comprises certain spinal nerve fibers from the lumbar and sacral regions and gives rise to the great sciatic nerve in the back of the thigh. See also spinal cord.
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Spinal nerves and spinal column

spi·nal nerves

(spī'năl nĕrvz) [TA]
The nerves emerging from the spinal cord; there are 31 pairs, each attached to the cord by two roots, anterior and posterior, or ventral and dorsal; the latter is provided with a circumscribed enlargement, the dorsal root (spinal) ganglion; the two roots unite in the intervertebral foramen, and the mixed spinal nerve almost immediately divides again into ventral and dorsal primary rami, the former supplying the anterolateral trunk and the limbs, the latter the true muscles and overlying skin of the back.
Synonym(s): nervi spinales [TA] .

spinal nerves

The 31 pairs of combined MOTOR and sensory nerves that are connected to the spinal cord.

spi·nal nerves

(spī'năl nĕrvz) [TA]
The nerves emerging from the spinal cord; there are 31 pairs, each attached to the cord by two roots, anterior and posterior, or ventral and dorsal.
Synonym(s): nervi spinales [TA] .
References in periodicals archive ?
This results from spinal nerve ligation producing attenuated glutamate uptake activity in the deep dorsal and ventral horn, the projection regions of excitatory, pain transmitting primary afferent neurons that utilize glutamate as an excitatory neurotransmitter (111).
When patients with spinal stenosis develop leg pain or cramping with ambulation, it usually is caused by mechanical compression and choking off of the microvascular supply to the spinal nerve.
What's even more impressive is the delicacy of our nervous system, made up of the brain, spinal cord, and spinal nerve roots.
The vertebral artery lies in close proximity to the C2, 3 and 4 spinal nerves, allowing it to be used as an ultrasonic landmark for identifying the deep cervical plexus.
The somatic nervous system innervates skeletal, or voluntary, muscles, and entails the brain, spinal cord, cranial nerves, and spinal nerves.
Joseph Bruner performed maternal-fetal surgery to fuse the spina bifida lesion (open wound) and protect her spinal nerves during the remaining weeks of gestation (womb development).
Just before entering the cord, the spinal nerves split into their sensory and motor components.
The dye circulates around the spinal cord and spinal nerves, which appear as white objects against bone on an x-ray film.
11] Thus, the phrenic nerve, being derived from spinal nerves of mixed motor and sensory function, could be the innovator (motor) of the cramp at a local or central level and the bearer (sensory) of the pain.
Lars Olson of the Karolinska Institute in Stockholm and his colleagues sliced a small section from the rats' spinal nerves, closed the gap with nerves from outside the spinal cord, glued the fibers in place, and biochemically coaxed severed spinal nerves to grow through this neural infrastructure.