A spinal cord is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal cord, one on each side of the vertebral column. These are grouped into the same cervical, thoracic, lumbar, sacral and spine regions. There are eight pairs of cervical nerves, twelve pairs of thoracic nerves, five pairs of lumbar nerves, five pairs of sacral nerves, and one pair of coccygeal nerve . The spinal cord is part of the peripheral nervous system.
Video Spinal nerve
Structure
Each spinal cord is a mixed nerve, formed from a combination of nerve fibers from the dorsal and ventral roots. The dorsal root is an afferent sensory root and carries sensory information to the brain. Ventral roots are the efferent motor roots and carry motor information from the brain. The spinal cord arises from the spine through the opening (the intervertebral foramen) between adjacent vertebrae. This is true for all spinal cord except for the first spinal cord (C1), which appears between the occipital bone and the atlas (first vertebra). Thus the cervical nerves are numbered by the vertebrae below, except for the C8 spinal nerve, which lies below the C7 vertebra and above the T1 vertebra. The thoracic, lumbar, and sacral nerves are then numbered by the vertebrae above. In the case of the lumbar S1 vertebra (aka L6) or the sacral L5 vertebra, the nerve is usually still calculated for L5 and the next nerve is S1.
Outside the vertebral column, the nerves divide into branches. The dorsal ramus contains nerves that serve the posterior portion of the trunk carrying visceral motors, somatic motors, and somatic sensory information to and from the skin and back muscles (episial muscle). The ventral ramus contains nerves that serve the anterior part of the stem and the upper and lower limbs (hypaxic muscles) carry visceral motors, somatic motors, and sensory information to and from the ventrolateral body surface, structures in the body wall, and limbs. The meningeal branch (recurrent meningeal nerve or sinuvertebralis) originates from the spinal nerve and reinserts the intervertebral foramen to serve ligaments, dura, blood vessels, intervertebral discs, facet joints, and periosteum vertebrae. Hemp communicantes contain autonomic nerves that serve visceral function of carrying motor and sensory visceral information to and from visceral organs.
Some anterior hemp join the adjacent anterior hemp to form the neural plexus, the interconnecting nerve tissue. The nerves that arise from the plexus contain fibers of various spinal cords, which are now brought together to several target locations. The major plexuses include the cervical plexus, brachialis, lumbar, and sacralis.
Maps Spinal nerve
Regional nerves
Cervical nerves
The cervical nerve is the spinal cord of the cervical vertebrae in the cervical segment of the spinal cord. Although there are seven cervical vertebrae (C1-C7), there are eight C1-C8 cervical nerves. All cervical nerves except C8 appear above the corresponding vertebrae, while the C8 nerve appears below the C7 vertebra. Elsewhere in the spine, nerves appear beneath the vertebra of the same name.
Posterior distribution includes the suboccipital nerve (C1), the larger occipital nerve (C2) and the third occipital nerve (C3). Anterior distribution includes cervical plexus (C1-C4) and brachial plexus (C5-T1).
The cervical nerves supply the sternohyoid, sternothyroid and omohyoid muscles.
A neural loop called an anode cervicalis is part of the cervical plexus.
Torque pain
The thoracic nerves are the twelve spinal cord arising from the thoracic vertebrae. Each T1-T12 thoracic nerve comes from below each thoracic vertebra. The branches also come out of the spine and directly into the paravertebral ganglia of the autonomic nervous system where they are involved in organ function and glands in the head, neck, chest and abdomen.
Anterior division: The intercostal nerve originates from the T1-T11 thoracic nerve, and runs between the ribs. In T2 and T3, the branch further forms an interostobrachial nerve. The subcostal nerve comes from the T12 nerve, and runs below the twelfth rib.
Posterior division: The medial branch (the medial ramus) of the posterior branch of the upper thoracic nerves runs between the semispinalis and multifidal dorsions, which they supply; they then penetrate the rhomboid and trapezius muscles, and reach the skin by the sides of the spinous process. This sensitive branch is called the medial skin ramus.
The medial branches of the lower six are distributed primarily to the multifidus and longissimus dorsi, sometimes removing the filaments to the skin near the midline. This sensitive branch is called the posterior cutaneous ramus.
Lumbar nerve
The lumbar nerve is the five spinal cord arising from the lumbar spine. They are divided into posterior and anterior divisions.
Posterior division : The medial branch of the posterior division of the lumbar nerve goes close to the articular process of the vertebra and ends in the multifidal muscle.
Lateral supply of spinae erector muscles.
The upper three secrete cutaneous nerves that penetrate aponeurosis from the latissimus dorsion on the lateral border of the spinae erector muscles, and descend posteriorly from the iliac crests to the buttocks, some of their branches running as far as the greater trochanter level.
Anterior division : An anterior division of the lumbar nerve (anterior rami) increases from top to bottom. They join, near their origin, by the gray ramie communicant of the lumbar ganglia of the sympathetic stem. This hemp is composed of long, slender branches that accompany the lumbar artery around the vertebral side of the body, under the psoas major. Their arrangements are somewhat irregular: one ganglion can give hemp to two lumbar nerves, or a lumbar nerve can receive hemp from two ganglia.
The first and second lumbar nerves, and sometimes the third and fourth respectively are connected to the lumbar portion of the sympathetic stem by the white ramus communion.
The nerve passes outwards sloping behind the psoas major, or between the fasciculi, distributing the filaments to it and the quadratus lumborum.
The first three and most of the four are connected together in this situation by the anastomotic loop, and form the lumbar plexus.
The smaller portion of the four combines with the fifth to form the lumbosacral rod, which aids in the formation of the sacral plexus. The fourth nerve is named after the furcal nerve, from the fact that it is shared between two plexuses.
Sacral nerves
The sacral nerve is the five pairs of spinal cord that comes out of the sacrum at the lower end of the vertebral column. This nerve root starts inside the vertebral column at the L1 vertebral level, where the cauda equina begins, and then down to the sacrum.
There are five sacral nerves paired, half of them arising through the sacrum on the left side and the other half on the right side. Each nerve arises in two divisions: one division through the anterior sacral foramen and the other through the posterior sacral foramen.
The nerves divide into branches and branches of different nerves joining each other, some of them also joining the branches of the lumbar or coccygeal nerves. This nerve anastomosis forms the sacral plexus and lumbosacral plexus. These plexus branches cause nerves that supply most of the hips, thighs, legs, and legs.
The sacral nerves have afferent and efferent fibers, so they are responsible for part of the sensory perception and movement of the lower extremities of the human body. From S2, S3 and S4 emerging pudendal fibers and potentially parasympathetic fibers supply the colon and rectum down, the bladder and the genital organs. These pathways have afferent and efferent fibers and, in this way, they are responsible for the conduction of sensory information from this pelvic organ to the central nervous system (CNS) and motor impulses from CNS to the pelvis that control the movement of these pelvic organs..
Coccygeal nerve
The coccygeal nerve is the 31st pair of spinal cord. It arises from the medullary conus, and the anterior root helps to form the coccygeal plexus. It is not divided into medial and lateral branches. It is distributed to the skin on the back of coccyx.
Function
Clinical interests
The muscles that one supply of the root of the spine are myotome nerves, and the dermatome is the area of ​​innervation of the skin for every spinal cord. Lesions of one or more nerve roots produce a characteristic pattern of neurologic defects (muscle weakness, abnormal sensation, reflex changes) that permit responsible localization of the lesion.
There are several procedures used in sacral nerve stimulation for the treatment of various related disorders.
Skiatika umumnya disebabkan oleh kompresi saraf lumbar L4, atau L5 atau saraf sakral S1, S2, atau S3, atau dengan kompresi saraf skiatik itu sendiri.
Gambar Tambahan
- Gambar diseksi
Referensi
Source of the article : Wikipedia
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