Flashcards in Anatomy and Physiology XV Deck (25)
Where do vertebral disc herniations typically occur?
Posterolaterally at L4-L5 or L5-S1 (p.427)
To what vertebral level does the spinal cord extend in adults?
To the lower border of L1-L2 vertebrae (p.427)
To what vertebral level does the subarachnoid space containing the CSF extend in adults?
Lower border of S2 vertebra (p.427)
Where is a lumbar puncture usually performed?
Between L3-L4 or L4-L5 (p.427)
What is the vertebral level of the cauda equina?
What type of information is transmitted via the dorsal columns of the spinal cord (DCML pathway)?
Pressure, vibration, fine touch, proprioception (p.427)
Name the two regions of the dorsal column tract?
Fasiculus cuneatus, faciculus gracilis (p.427)
What is the difference in information transmitted via the fasiculus cuneatus vs. fasiculus gracilis?
Gracilis- more medial; lower body and legs; Cuneatus- more lateral; upper body and arms (p.427)
Describe the layout of information in the lateral corticospinal tract.
Upper body/ arms is more medial; lower body/ legs is more lateral (p.427)
What type of information is transmitted via the lateral corticospinal tracts?
Descending voluntary motor information (p.427)
In what vertebral levels are the intermediate horn sympathetics located?
What type of information is transmitted via the anterior spinothalamic tract?
Crude touch, pressure (p.427)
Describe the layout of information in the anterior spinothalamic tract.
Cervical information is more medial to sacral information (p.427)
Describe the location and path of the first order neuron in the dorsal column medial leminiscus pathway.
Sensory nerve ending --> cell body in dorsal root ganglion --> enters spinal cord, ascends ipsilaterally in dorsal column (p.428)
Compare the types of information carried in the lateral spinothalamic tract to that carried in the anterior spinothalamic tract.
Lateral: pain, temperature; anterior: crude touch, pressure (p.428)
Describe the location and path of the first order neuron in the spinothalamic tract pathway.
Sensory nerve endings (Adelta and C fibers) (with cell bodies in the dorsal root ganglion) --> Enters spinal cord (p.428)
What is the difference in information passage between the lateral corticospinal tract and the DCML/spinothalamic tracts?
DCML/ Spinothalamic --> ascending information flow; Lateral corticospinal tract --> descending information flow (p.428)
Describe the location and path of the first order neuron information flow in the lateral corticospinal tract.
UMN has a cell body in the primary motor cortex --> decends ipsilaterally through internal capsule until decussating at the caudal medulla (pyramidal decussation) --> descends contralaterally (p.428)
Where is the first synapse in the DCML spinal pathway?
Ipsilateral nucleus cuneatus or gracilis (of the medulla) (p.428)
Where is the first synapse in the Spinothalamic tract?
In the ipsilateral gray matter of the spinal cord (p.428)
Where is the first synapse in the Lateral corticospinal tract?
In the cell body of the anterior horn of the spinal cord (p.428)
Describe the location and path of the second order neuron in the DCML pathway.
Decussates in the medulla and ascends contralaterally in the medial lemniscus (p.428)
Describe the location and path of the second order neuron in the spinothalamic tract pathway.
Decussates at the anterior white commissure and ascends contralaterally (p.428)
Describe the location and path of the second order neuron in the lateral corticospinal tract pathway.
LMN leaves the spinal cord (p.428)