Neuro12 Flashcards
Spinal Nerves Spinal Cord UMN vs LMN lesions
How many spinal nerves are there?
31 total
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal
How do the nerves correspond to the vertebrae?
C1-C7 exit ABOVE corresponding vertebra
All other nerves exit BELOW
(e.g., C3 exits above the 3rd cervical vertebra; L2 exits below the 2nd lumbar vertebra)
What is a Vertebral Disc Herniation?
Nucleus Pulposus (soft central disc) herniates through Anulus Fibrosus (outer ring)
Where does a vertebral disc herniation typically occur?
Posterolaterally @ L4-L5 or L5-S1
In adults, where does the spinal cord extend to?
lower border of L1-L2 vetebrae
In adults, the subarachnoid space (containing CSF) extends to?
Lower border of S2
In adults, where are Lumbar Punctures usually performed?
Between L3-L4 or L4-L5 (level of cauda equina)
“to keep the cord alive, keep the spinal needle between L3 and L5”
What information is being processed through the Dorsal Columns?
Pressure, Vibration, Touch, Proprioception
What are the two regions of the Dorsal Columns?
- Fasciculus Cuneatus
- Upper body, Extremities
- Lateral
- Faciculus Gracilis
- Lower body, Extremities
- Medial
“Arms outside, legs inside”
What spinal cord tract is involved in Voluntary Motion?
Lateral Corticospinal tract
How is the lateral corticospinal tract arranged?
“Legs are Lateral in Lateral Corticospinal tract”
*Arms are medial
What spinal cord tract is involved in pain & temperature?
Lateral spinothalamic tract
Where do Afferent Pain fibers enter the spinal cord?
Posterior Horn
What is true of all ASCENDING spinal cord tracts?
They SYNAPSE then they CROSS
Upper Motor Neuron Vs. Lower Motor Neuron:
-Weakness
Both
