L20 Flashcards
Where does the spinal cord begin and finish
-Begins foramen magnum
ends at lumbar vertebra 1 (L1)
Where is the spinal cord?
-Sits within a meningeal sac situated within the spinal canal.
where does the spinal cavity end?
Coccygeal vertebrae
What are the parts labelled and their function
-Extension of meningeal sac filled with CSF
-Conus medularis: Attachment point for filum terminale
-Filum terminale: extends from conus medularis to end of spinal cavity (Coccygeal)
Anchors spinal cord
How many spinal nerves are attached to the left and right of the spinal cord?
8, 12, 5,5,1
How are spinal nerves named? and what is the exception?
Named by vertebra they exit below eg T5 (spinal nerve exits under the 5 thoracic vertabra)
Exception is the first cervical spinal nerve, C1, which exits between the skill and first cervical vertabra
What is the cauda equina?
‘tail’ collection of long nerves inferior to spinal cord to reach appropriate exit point
How to tell the direction of spinal cord?
Sharp ends of butterfly is pointing posterior and the large median fissure is on the anterior side
Name points
-Posterior median sulcus
-White matter (axons)
-Grey matter (cell bodies)
-Central canal
-Anterior median fissure
What are the two main coloured parts in spinal cord and what are the names?
-Butterfly: Horns (grey matter)
-Columns (white matter)
What are the parts of the horns?
Dorsal Horn
Lateral Horn
Ventral Horn
What are the parts of the columns?
Dorsal column
Lateral column
Ventral column
Name its parts
Dorsal root
Dorsal root ganglion (cell bodies)
Ventral nerve root
Spinal nerve
Which direction does types of information flow within the spinal cord?
-Dorsal side: Sensory (afferent) Dorsal nerve root carries infor from PNS to CNS
-Ventral side: Motor (Efferent) Ventral Nerve root carries info from CNS to PNS
Where does info flow out of spinal cord, Efferent
Blue (lateral horn): autonomic neurons (cell bodies)
Red (ventral horn): Somatic motor neurons (cell bodies)
Info flows out of spinal cord into ventral nerve roots, into spinal nerve then to effector
What happens if Somatic motor neurons labelled X is damaged
Paralysis of muscles from the somatic motor neurons on the same side on the body
What is in the dorsal root ganglion? and what type of neuron is is?
Cell bodies of sensory neurons
unipolar neuron
What would happen if there was damage on dorsal horn
loss of sensation from regions of body supplied by sensory neurons from this spinal cord segment on same side only
Visualise this flow of information in this diagram
What is the dorsal ramus?
The branch from spinal nerve directed posteriorly
Efferent and Afferent information flows from the back
What is ventral ramus
The branch pointing to the right
-Efferent and afferent information flows from ventral body
What is rami communicans?
Branch pointing downwards separating into 2 smaller ones and rejoining into sympathetic chain ganglion
Structure of peripheral nerve (PNS Bundles of axons)
Order from smallest to largest: Endo, Peri, Epi
Endoneurium: Covering axons
Bundles of Axons: Fascicle
Perinuerium: Covers fascicle
Bundles of fascicles: nerve
Epineurium: covers nerve
smalles to largest: Axon, Endo, Fasicle, Peri, Nerve, Epi
