T3: SPINAL CORD Flashcards
What is the cone-shaped end of the spinal cord?
Conus Medullaris
A space filled with CSF and contains the Cauda Equina
Subarachnoid Space
A bundle of spinal nerves in the conus medullaris at the L2 SC segment level
Cauda Equina/’Horse Tail”
The dura mater which extends to S2, is known as?
Dural Sheath
What is located between the dura and inferior surface of the neural canal, where an “epidural injection” is inserted?
Epidural Space
The area of the spinal cord which a pair of dorsal and ventral roots arise
SC Segments
A formation of the anterior and posterior roots joining together, to form a bony channel between adjacent vertebrae, to form a spinal nerve
Intervertebral Foramen
Which root carries Afferent information?
Dorsal/Posterior Root
Which root carries Efferent information?
Ventral/Anterior Root
The Ventral Root carries Efferent information to the…?
Spinal Cord to Muscles and Viscera
The lumbar and sacral spinal nerve roots below the conus medullaris form the…?
Cauda Equina
How many pairs and segments of spinal nerves are there?
31 pairs/segments
What divides the spinal cord into right and left sides?
- Anterior Median Fissure
- Posterior Median Sulcus
Consists of cell bodies of neurons, neuroglia, unmyelinated axons and the dendrites of interneurons and motor neurons.
Gray Matter
Filled with CSF and runs longitudinally through the length of the entire spinal cord. And contiguous with the ventricular system of the brain
Central Canal
Which horn contains the cell bodies of lower motor neurons (LMN)?
Ventral/Anterior Horn
What is the “collective term” for the brainstem and SC?
Neuraxis
What does the LMNs in the cranial nerves innervate?
Muscles of the head
LMNs leave the SC to innervate..?
Muscles of the body
The lateral horn is present at the ___ levels of the spinal cord, specifically through _______ vertebra
14 Levels
T1 - L2
What system outflow is via the T1-L2 cell bodies in the lateral horn?
Sympathetic NS
What is the Sympathetic NS referred to as?
Thoracolumbar Outflow
LMN are motor neurons whose cell bodies are found in the? (2 locations)
- Ventral Horn
- Cranial Nerve Nuclei of the brainstem
What innervates the LMN, and its “link”.
- Innervates skeletal muscle fibres for all voluntary movement
- Act as a link between UpperMN and muscles
A LMN type that innervate extrafusal fibres - involved in muscle contraction
Alpha Motor Neurons
A LMN type that innervates intrafusal muscle fibres, with 1a sensory afferents compose muscle spindles.
Sensing body proprioception.
Gamma Motor Neurons
Bundled axons in the CNS
Tracts
Sensory tracts travel toward the brain
Ascending Tracts
Motor tracts travel away from the brain
Descending Tracts
