2-E Spinal Meninges and Cord Flashcards
Where along the spinal cord are there enlargements for limb innervation?
cervical C4-T1 and lumbosacral T11- S1
T/F Spinal cord levels do not necessarily correspond with vertebral column levels
TRUE
How are spinal nerves are numbered relative to the vertebrae
Spinal nerve names do line up with the vertebral level: cervical spinal nerves exit superior to vertebra, throracic, lumbar and sacral spinal nerves exit superior to vertebrae
What is the conus medullaris
inferior tip of the spinal cord
What is the cauda equina.
“horse tail of caudal nerve roots running longer than the spinal cord itself
What are the distinguished parts of the spinal cord gray matter where cell bodies are located?
dorsal horn, lateral horn and ventral horn
Define nerve
a nerve is a group of axons/ fibers plus connective tissue
What do you call the place that two spinal nerves meet to exchange fibers
plexus
Draw a diagram including the folllowing parts: dorsal and ventral roots, dorsal root ganglion, dorsa and ventral ramous, posterior cutaneous branch, intercostal nerves with lateral and anterior cutaneous brances
Netter 185
Name the three components of spinal nerve
somatomotor, post synaptic sympathetic (visero sensory) and somato sensory (general sensory)
Define somatomotor
innervates skeletal muscle (voluntary)
Define viscerosensory nerves
are post synaptic fibers, bring sensory feedback from organs
Where are the cell bodies for the somatomotor, viscerosensory and somatosensory
ventral horn, lateral horn and DRG and dorsal horn respectively
Define dermatome
area of skin innervated by a single spinal nerve
Locate landmark dermatomes T-4, T10a dn T12
nipple line, umbillical line and bikini line
Where does the shingles virus live?
DRG
Describe the spinal dura, arachnoid and pia mater
dura mater (tough fibrous outer covering), arachnoid (pressed up against the dura, connected by tight junctions) pia mater is a very thin and vascular membrane that covers the spinal cord directly
State the location and function of the : arachnoid trabeculae
below the arachnoid layer, spider web like fibrous space : filled with CSF: trabeculae connect to pia mater and support the subarachnoid space
State the location and function of the denticulate ligament
connection between the dura and pia mater, made of pia mater and occurs between the ventral and doral roots
State the location and function of the filum terminale
interanlly is pia mater, externally is pia and dura, anchors the spinal cord to the coccyx
State the position and contents of the epidural space
outside the dural mater contains fat and loose connective tissue and epidural veous plexus
State the position and contents of the subdural space
very small space that is usually only apparent during pathology, fills with serous fluid
Where is the lumbar cistern
caudal to the medullary cone (L2-S4)
Describe where a lumbar puncture is performed ideally.
between spinous processes of L3/L4 or L4/L5, needle puncture dura and arahnoid maters
What is the difference between an epidural block and a spinal block
anesthesia is placed in the epidural space and the subaracnoid space respectively
Describe the two parts of the arachnoid.
arachnoid barrier: flattened cells bound together by tight junctions; trabeculae: fine web-like connections to the dura mater
Where is the largest subarachnoid space?
L2 which also contains the cauda equine
