HS1-5 Spinal Cord Flashcards
Where, in terms of vertebrae, does the spinal cord end in adults?
ends at L1-L2 vertebral level in adults
What is referred pain?
pain felt at a site other than the site where it is caused
What are the three largest plexuses in the body?
cervical; brachial; lumbosacral
Define dermatome.
area of skin innervated by a single spinal nerve
Define myotome.
group of muscles innervated by single spinal nerve
What is the cervical enlargement?
results from large # of neurons required to innervate upper limbs, extending from C5 to T1
Where is the cervical enlargement widest?
opposite C6
What is the lumbosacral enlargement?
results from large # of neurons required to innervate lower limbs, extending from L1 to S1
Where is the lumbosacral enlargement widest?
opposite T12
Describe the ventral/anterior horn of gray matter.
contains motor neurons that supply skeletal muscles; contains interneurons responsible for reflexes and coordination of movement
Describe the dorsal/posterior horn of gray matter.
mainly contains interneurons and projection neurons
The dorsal/posterior horn of gray matter is primarily concerned with
processing of sensory information
Where are preganglionic sympathetic neurons located?
intermediate gray matter
How many spinal nerves are there?
31
How is each spinal nerve connected to the spinal cord?
via two roots — a ventral/anterior one and a dorsal/posterior one
What kind of axon does the ventral root carry?
efferent (outgoing) motor axons
Where in the spinal cord are the cell bodies of efferent motor axons found?
in the gray matter
What kind of axon does the dorsal root carry?
afferent (incoming) sensory axons
Where are the cell bodies of sensory axons found?
in the dorsal root ganglia, near the intervertebral foramen
What is the outermost meningeal layer?
dura mater
What are the attachments of the spinal dural sac?
foramen magnum of cramium superiorly, and inferiorly to the coccyx
Where does the spinal dural sac end?
S2-S3 level
What is the intermediate meningeal layer?
arachnoid mater
In what space is CSF found?
subarachnoid space






