spinal nerve
Học thuậtThân thiện
Definition
Noun: A spinal nerve is one of the 31 paired nerves that originate from the spinal cord. Each nerve is formed by the union of two distinct roots: a ventral (anterior) root carrying motor signals away from the cord, and a dorsal (posterior) root carrying sensory signals toward the cord. These nerves exit the vertebral column through openings between the vertebrae and serve specific regions of the body.
Usage and Examples
Basic Usage:
- Damage to a spinal nerve can cause pain, numbness, or weakness in the area it supplies.
- The doctor explained that the tingling in her arm was due to a compressed spinal nerve.
In Anatomical Context:
- Each spinal nerve is a mixed nerve, containing both sensory and motor fibers.
- The spinal nerves are part of the peripheral nervous system.
Advanced Usage
- Clinical/Medical Context:
- The term is used to specify the location and function of nerve damage or involvement in conditions like sciatica (involving the sciatic nerve, formed from several spinal nerves) or a herniated disc.
- The MRI showed a herniation pressing on the L5 spinal nerve root.
Variants and Related Words
- Spinal Nerve Root: Refers specifically to the ventral or dorsal root before they merge to form the spinal nerve proper.
- Nerve Root: A more general term that can refer to the roots of spinal nerves or cranial nerves.
- Spinal Cord: The central structure from which the spinal nerves emerge.
- Peripheral Nerve: A broader category that includes spinal nerves and other nerves outside the brain and spinal cord.
Synonyms
- Nerve (in a specific anatomical context, though this is a much broader term).
- There are no direct one-word synonyms for this precise anatomical structure.
Related Phrases
- Spinal nerve plexus: A network where spinal nerves intertwine and reorganize, such as the brachial or lumbar plexus.
- Spinal nerve impingement: A condition where a spinal nerve is compressed or irritated.
- Spinal nerve foramen: The opening in the vertebra through which a spinal nerve exits.
Noun
- any of the 31 pairs of nerves emerging from each side of the spinal cord (each attached to the cord by two roots: ventral and dorsal)