(Ch.13) Lesson 17: The spinal cord & spinal nerves Flashcards
(117 cards)
How many spinal cord segments are there?
31 spinal cord segments
Where are spinal cords based?
Based on vertebrae where spinal nerves originate.
Do the positions of the spinal & vertebrae segments change?
Yes, they change w/ age
Why do the vertebrae & spinal segments change as you age?
As you age the vertebral column grows & ventral roots elongate.
How are cervical roots named?
They are named for the vertebra inferior to it
* The spinal nerve exits above the vertebrae it is named after
* All other nerves are named after their superior vertebra.
What are the 2 roots/branches of the spinal nerves?
- Ventral
- Dorsal
Ventral =
Axons of motor neurons
*Somatic and visceral effectors
Dorsal =
Axons of sensory neurons
Where is there spinal nerve located?
Found @ each side of the spine
1. Dorsal and ventral roots joins
2. Spinal nerve formed.
Dorsal roots + ventral roots =
Formation of spinal nerve
What do mixed nerves carry?
Carry afferent and efferent sensory fibers
What do mixed nerves carry?
Axons from ventral & dorsal roots
Explain what the spinal meninges specialize in.
Membranes the isolate spinal cord from the surroundings
What do the spinal meninges interact with?
Interact with the cranial meninges
What are the functions of the spinal meninges?
- Protecting the spinal cord
- Carrying blood to epidural & subarachnoid space
Explain what is meningitis
- Viral or bacterial meningitis
- Spinal meningitis or cerebral meningitis could disrupt CSF flow, damage or kill neurons & neuroglia
How does meningitis impact the body @ later stages?
Later stages of meningitis affect the entire meningeal system.
What are the 3 meningeal layers (in order of inner-outer)?
- Dura
- Arachnoid
- Pia
What are the physical characteristics of Dura mater?
- Tough & fibrous
- Cranially…
-Fuses w/ periosteum of occipital bone
-Continuous w/ dura mater - Caudally…
-Tapers w/ dense collagen fibers
- Joins filum terminal in coccygeal ligaments
Which space is located within the dura mater?
The epidural space
What is the epidural space?
The space between spinal dura mater and walls of vertebral canal/foramen
What type of tissue does the epidural tissue contain?
Contains loose connective tissue and adipose tissue
The epidural is which kind of site?
Anesthetic injection site