| Sacral spinal nerve | |
|---|---|
 The plan of the lumbosacral plexus | |
| Details | |
| Identifiers | |
| Latin | nervi spinalis |
| FMA | 6427 |
| Anatomical terminology | |
The sacral spinal nerve 5 (S5) is a spinal nerve of the sacral segment. [1]
It originates from the spinal column from below the 5th body of the sacrum.
S5 supplies the coccygeus muscle.
The peripheral nervous system (PNS) is one of two components that make up the nervous system of bilateral animals, with the other part being the central nervous system (CNS). The PNS consists of nerves and ganglia, which lie outside the brain and the spinal cord. The main function of the PNS is to connect the CNS to the limbs and organs, essentially serving as a relay between the brain and spinal cord and the rest of the body. Unlike the CNS, the PNS is not protected by the vertebral column and skull, or by the blood–brain barrier, which leaves it exposed to toxins.
Tetraplegia, also known as quadriplegia, is defined as the dysfunction or loss of motor and/or sensory function in the cervical area of the spinal cord. A loss of motor function can present as either weakness or paralysis leading to partial or total loss of function in the arms, legs, trunk, and pelvis; paraplegia is similar but affects the thoracic, lumbar, and sacral segments of the spinal cord and arm function is retained. The paralysis may be flaccid or spastic. A loss of sensory function can present as an impairment or complete inability to sense light touch, pressure, heat, pinprick/pain, and proprioception. In these types of spinal cord injury, it is common to have a loss of both sensation and motor control.
The sciatic nerve, also called the ischiadic nerve, is a large nerve in humans and other vertebrate animals which is the largest branch of the sacral plexus and runs alongside the hip joint and down the lower limb. It is the longest and widest single nerve in the human body, going from the top of the leg to the foot on the posterior aspect. The sciatic nerve has no cutaneous branches for the thigh. This nerve provides the connection to the nervous system for the skin of the lateral leg and the whole foot, the muscles of the back of the thigh, and those of the leg and foot. It is derived from spinal nerves L4 to S3. It contains fibers from both the anterior and posterior divisions of the lumbosacral plexus.
A spinal nerve 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 nerves, one on each side of the vertebral column. These are grouped into the corresponding cervical, thoracic, lumbar, sacral and coccygeal regions of the spine. 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 nerves. The spinal nerves are part of the peripheral nervous system.
Neuromeres are distinct groups of neural crest cells, forming segments in the neural tube of the early embryonic development of the brain. There are three classes of neuromeres in the central nervous system – prosomeres, mesomeres and rhombomeres that will develop the forebrain, midbrain, and hindbrain respectively.
A dermatome is an area of skin that is mainly supplied by afferent nerve fibres from the dorsal root of any given spinal nerve. There are 8 cervical nerves , 12 thoracic nerves, 5 lumbar nerves and 5 sacral nerves. Each of these nerves relays sensation from a particular region of skin to the brain.
The filum terminale is a delicate strand of fibrous tissue, about 20 cm in length, extending inferior-ward from the apex of the conus medullaris to attach onto the coccyx. The filum terminale acts to anchor the spinal cord and spinal meninges inferiorly.
S5 or S-5 may refer to:
A nerve plexus is a plexus of intersecting nerves. A nerve plexus is composed of afferent and efferent fibers that arise from the merging of the anterior rami of spinal nerves and blood vessels. There are five spinal nerve plexuses, except in the thoracic region, as well as other forms of autonomic plexuses, many of which are a part of the enteric nervous system. The nerves that arise from the plexuses have both sensory and motor functions. These functions include muscle contraction, the maintenance of body coordination and control, and the reaction to sensations such as heat, cold, pain, and pressure. There are several plexuses in the body, including:
The perforating cutaneous nerve is a cutaneous nerve of the sacral plexus that provides sensory innervation to the skin of the buttocks.
A nerve root is the initial segment of a nerve leaving the central nervous system. Nerve roots can be classified as:
Pelvic splanchnic nerves or nervi erigentes are splanchnic nerves that arise from sacral spinal nerves S2, S3, S4 to provide parasympathetic innervation to the organs of the pelvic cavity.
The coccygeal plexus is a small nervous plexus upon the pelvic (anterior) surface of the coccygeus muscle.
The ventral ramus is the anterior division of a spinal nerve. The ventral rami supply the antero-lateral parts of the trunk and the limbs. They are mainly larger than the dorsal rami.
The sacral spinal nerve 4 (S4) is a spinal nerve of the sacral segment.
The sacral spinal nerve 3 (S3) is a spinal nerve of the sacral segment.
The sacral spinal nerve 2 (S2) is a spinal nerve of the sacral segment.
The sacral spinal nerve 1 (S1) is a spinal nerve of the sacral segment.
The spinal cord is a long, thin, tubular structure made up of nervous tissue that extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone) of vertebrate animals. The center of the spinal cord is hollow and contains a structure called the central canal, which contains cerebrospinal fluid. The spinal cord is also covered by meninges and enclosed by the neural arches. Together, the brain and spinal cord make up the central nervous system.
Tarlov cysts, are type II innervated meningeal cysts, cerebrospinal-fluid-filled (CSF) sacs most frequently located in the spinal canal of the sacral region of the spinal cord (S1–S5) and much less often in the cervical, thoracic or lumbar spine. They can be distinguished from other meningeal cysts by their nerve-fiber-filled walls. Tarlov cysts are defined as cysts formed within the nerve-root sheath at the dorsal root ganglion. The etiology of these cysts is not well understood; some current theories explaining this phenomenon have not yet been tested or challenged but include increased pressure in CSF, filling of congenital cysts with one-way valves, inflammation in response to trauma and disease. They are named for American neurosurgeon Isadore Tarlov, who described them in 1938.
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