neuro 22

Question 1

anterior gray matter

Answer 1

alpha motor neurons and motor fibers innervation skeletal muscles

Question 2

in the lateral portion of the SC white matter

Answer 2

descending corticospinal tract

Question 3

where does the CST cross

Answer 3

in he medulla

Question 4

where does the CST synapse?

Answer 4

on alpha motor neurons in the anterior horn

Question 5

dorsal columns do what

Answer 5

ascending tracts that mediate joint position sense

Question 6

where do dorsal columns cross

Answer 6

the brainstem

Question 7

where does the spinothalamic tract run?

Answer 7

anterolateral

Question 8

what info does the spinothalamic tract carry?

Answer 8

pain and temp

Question 9

where does the Spinothalamic tract synapse?

Answer 9

come into the SC and then synapse within two levels and then cross the cord an dascend contralateral to the limbs from which they originated

Question 10

motor nerve roots

Answer 10

anterior in the SC

Question 11

sensory nerve roots

Answer 11

posterior in the SC

Question 12

where do the CERVICAL nerve roots exit the canal?

Answer 12

just above the corresponding vertebrae

Question 13

why is there no C8 vertebra?

Answer 13

C8 nerve exits just above the T1

Question 14

does C1 have sensory fibers?

Answer 14

nope

Question 15

below the cervical region, where do the nerves exit the canal?

Answer 15

below their corresponding vertebal bodies

Question 16

the corresponding level of the cord itself is typically where in relation to the root?

Answer 16

the level of the cord is typically a few bony levels above the root; for example, the T10 cord may lie adjacent to the T8 vert

Question 17

where does the spinal cord ent?

Answer 17

L1 vertebral level

Question 18

where do the dorsal columns cross?

Answer 18

brainstem

Question 19

where does the spinothalamic tract cross?

Answer 19

in the cord, near the level of entry

Question 20

transection at what spinal cord level gives you respiratory insuff

Answer 20

above C3-C5; and Horner’s may also develop due to transit of symp fibers up here

Question 21

abdominal reflexes are lost with lesions above what?

Answer 21

T6

Question 22

bowel and bladder dysfunction may follow lesions above what?

Answer 22

sacral spinal cord level

Question 23

intramedullary

Answer 23

within the SC

Question 24

common causes of cord compression

Answer 24

bony lesions from metastatic cancer, esp breast and prostate

Question 25

Brown-Sequard syndome

Answer 25

hemicord

Question 26

loss of proprioception and light touch ipsilateral, motor ipsi, and pain and temp contra

Answer 26

hemicord lesion

Question 27

what does a central SC lesion affect?

Answer 27

spinothalamic tract fibers crossing at the level of the lesion; deficits in pain and temp are bilateral and over several segments

Question 28

what is a "dissociated" sensory loss

Answer 28

pain and temp sesation are affected but proprioception ang light touch are not; seen in central cord lesions

Question 29

syringomyelia

Answer 29

expanison of the potential fluid space in the center of the SC, usually over several levels

Question 30

cape-like loss of pain and temp sensation

Answer 30

syringomyelia

Question 31

syringomyelia often assoc with what?

Answer 31

posterior skull and brain malformations such as Chiari malformations

Question 32

syringobulbia

Answer 32

when the syrinx extends into the brainstem causing brainstem neuro signs

Question 33

treatment of syringomyelia

Answer 33

drain with a shunt; controversial

Question 34

hematomyelia

Answer 34

bleeding into the center of the cord

Question 35

central cord syndrome symptoms

Answer 35

moor and sensory dysfunction below the lesion and often cape=like loss of pain and temp at levels near the lesion

Question 36

radiation myelopathy

Answer 36

develops 6 months to years after radiotherapy

Question 37

syphilis affects what part of the spinal cord

Answer 37

posterior columns (tabes dorsalis)

Question 38

Vit b12 def

Answer 38

affects posterior columns

Question 39

cauda equina lesions

Answer 39

affect the spinal nerve roots with the spinal canal in the lumbar and sacral regions without affecting the spinal cord itself;

Question 40

how do cauda equina lesions present

Answer 40

wasting, weakness, and fasciculations in muscles innervated by these roots, often with lots of pain

Question 41

what causes cauda equina syndromes?

Answer 41

narrowing or obstruction of the SC in the lumbosacral region, by infections and by central disks below the level of the SC

Question 42

conus medullaris

Answer 42

the tip of the SC; this includes the centers controlling bowel, bladder, and sex function

Question 43

how do conus lesions present?

Answer 43

may affect bowel, bladder, and sex function; and if they remain below the lubar cord, may leave leg strength and reflexes intact

Question 44

blood supply for anterior two-thirds of the SC

Answer 44

anterior spinal artery

Question 45

what does the anterior spinal artery arise from?

Answer 45

branches of the two vertebral arteries, that join at the top the cord

Question 46

caudally, what is the largest single artery supplyng the ASA?

Answer 46

artery of Adamkiewicz, fed by perforating arteries from the aorta entering the SC at about the L2 level

Question 47

what supplies the anterior horns and corticospinal tracts

Answer 47

SA

Question 48

what supplies the dorsal columns posteriorly

Answer 48

plexus of many arteries, in turn fed by segmental arteries that arise from aorta and course along the ribs, giving off radicular arteries next to the nerve roots near the cord

Question 49

anterior spinal artery syndrome

Answer 49

stroke of the ASA; weakness below the lesion and there may be intense radicular pain or back pain and sphincter dysfunction; no loss of position sense

Question 50

which part of the SC is the least well perfused

Answer 50

thoracic cord, so it is most susceptible to stroke

Question 51

where is the border between the bascular supply from the vertebral arteries above and the ASA inferiorly

Answer 51

T4; systemic hypotension can lead to a watershed infarct here

Question 52

common causes of ASA syndrome

Answer 52

aortic surgery and atherosclerosis

Question 53

spinal shock

Answer 53

flaccid weakness and complete absence of DTRs immediately after trauma; spasticity typically develops over the next few days or weeks

Question 54

what treatment fo traumatic cord compression

Answer 54

high doses of methylprednisolone

Question 55

treatment for compression of SC due to tumors

Answer 55

high dose dexamtehasone

Question 56

surgical decompression of the SC

Answer 56

of uncertain benefit

Question 57

ALS

Answer 57

aka Lou Gherig's disease; extensive neuro loss, mostly within the SC but also some dementia

Question 58

cause of ALS

Answer 58

unkonwn, about 10% genetic

Question 59

what neurons are involved in ALS?

Answer 59

alpha motor neurons (LMNs) and also cortical motor nerons and lateral corticospinal tracts

Question 60

what does amyotrophic mean

Answer 60

loss of muscle mass from denervation and lateral to the CST dysfunction

Question 61

does ALS cause sensory dysfunction

Answer 61

no

Question 62

eye movements in ALS

Answer 62

remain normal

Question 63

prognosis of ALS

Answer 63

typically fatal within 3-5 years

Question 64

Riluzole

Answer 64

retards the speed of deteriortation in ALS somewhat does not reverse it

Question 65

primary lateral sclerosis

Answer 65

primaruly lateral CST dysfunction, producing spastiicty and loss of motor control without prominent alpha motor neuron loss

Question 66

SMA

Answer 66

spinal muscular atrophies (SMAs) affect primarily the alpha motor neurons; anterior horn cell degeneration

Question 67

Wednig-Hoffman disease

Answer 67

an SMA presenting in infancy

Question 68

chiari formation

Answer 68

downward protrusion of the medulla with or witout the cerebellum through the foramen magnum

Question 69

dysraphisms

Answer 69

failure of proper closure fo the neural tibe can result in tis midline structural deficit

Question 70

Hypertrophy of the filum terminale

Answer 70

produces a "tethered cord syndrome" with pain and dysfunction of the SC, esp at lower levels

Question 71

herniated disks most common in what region?

Answer 71

cervical

Question 72

treatment of herniated disk

Answer 72

surgical removal of the disc, but some extruded disks are reversible on their own with time

Question 73

spondylolisthesis

Answer 73

one vertebra displaced onto another

Question 74

lytic lesions of the vertebra

Answer 74

from mets; can lead to SC compression

Question 75

a "sensory level to T6" means

Answer 75

he can't feel below T6; means the lesion is at or above this level