B7-021 Spinal Cord Injury

Question 1

responsible for bladder/bowel retention

Answer 1

SNS

Question 2

responsible for bladder/bowel emptying

Answer 2

PNS

Question 3

what is the effect of SNS on the bladder walls and sphincter?

Answer 3

relaxation of bladder walls
constriction of sphincter

Question 4

what is the effect of PNS the bladder walls and sphincter?

Answer 4

contraction of bladder walls
relaxation of sphincter

Question 5

where do the PNS preganglionic neurons that control bowel/bladder function reside?

Answer 5

sacral cord (S2-S4)

Question 6

where do the SNS preganglionic neurons that control bowel/bladder function reside?

Answer 6

thoracic and upper lumbar cord

Question 7

sensory afferents to the bowel and bladder enter at the […] cord

Answer 7

sacral

Question 8

controls the detrusor muscles in the bladder

Answer 8

frontal micturition inhibiting area

(in cortex)

Question 9

controls the activity of sphincters

Answer 9

sensorimotor sphincter control area

(in cortex)

Question 10

region in the pons that organizes functional activity of the bowel/bladder

Answer 10

pontine micturition center

Question 11

allows changes to bowel/bladder function under voluntary control from the cortex

Answer 11

pontine micturition center

Question 12

the parasympathetic preganglionic neurons that control emptying the bladder are located in the […] cord

Answer 12

sacral

Question 13

the sympathetic preganglionic neurons that control bladder retention are located in the […] cord

Answer 13

lower thoracic/upper lumbar

Question 14

smooth muscle bladder structures under the control of the autonomic nervous system [2]

Answer 14

detrusor muscle
internal sphincter

Question 15

the external sphincter is under […] muscle control

Answer 15

voluntary

Question 16

in order for the parasympathetic nervous system to allow for bladder emptying, the detrusor must [….] and the internal sphincter must […]

Answer 16

detrusor must contract
internal sphincter must relax

Question 17

in order for the sympathetic nervous system to allow for retention, the detrusor must [….] and the internal sphincter must […]

Answer 17

detrusor must relax
internal sphincter must contract

Question 18

send information about the state/stretch of the bladder to higher centers

Answer 18

sensory neurons

Question 19

the origin of the sympathetic innervation to the bladder

Answer 19

IMLC synapses at inferior mesenteric ganglion

Question 20

the origin of the parasympathetic innervation to the bladder

Answer 20

pons –> sacral cord

Question 21

innervates the external sphincter

Answer 21

pudendal nerve

Question 22

the origin of voluntary motor innervation to the bladder

Answer 22

pons –> ventral horn of sacral cord –> pudendal nerve —> external sphincter

Question 23

a reflex loop in the spinal cord allows for [….] of the bladder

Answer 23

reflex emptying

(like in a baby, before these pathways are well developed)

Question 24

lesions between the pons and sacral cord will cause symptoms similar to

Answer 24

UMN lesions

Question 25

flaccid, acontractile bladder overflow incontinence due to laughing, sneezing, coughing, etc

Answer 25

acute central lesion or peripheral lesion (catheterization can help prevent overflow)

Question 26

hyperreflexic bladder low urine volume

Answer 26

chronic central lesions

Question 27

carries touch, vibration, and sensory information from the skin to the primary somatosensory cortex

Answer 27

DC/ML

Question 28

carries voluntary motor signals from the motor cortex to the peripheral neurons

Answer 28

corticospinal tract

Question 29

carries pain and temperature information from the skin to the primary somatosensory cortex

Answer 29

spinothalamic tract

Question 30

things to consider when localizing lesions [4]

Answer 30

1. what side of the body is affected? 2. what region (level) of the body is affected? 3. what sensory is affected? 4. what motor is affected?

Question 31

lesions in the spinal cord of the spinothalamic pathway will produce [...] deficits

Answer 31

contralateral

Question 32

lesions in the spinal cord of the corticospinal and DC/ML pathways will produce [...] deficits

Answer 32

ipsilateral

Question 33

spastic paralysis hyperactive reflexes little atrophy indicates damage in

Answer 33

UMN

Question 34

flaccid paralysis hypoactive reflexes atrophy indicates damage in

Answer 34

LMN

Question 35

constellation of symptoms ocurring after spinal cord hemisection is called [....]

Answer 35

Brown-Sequard syndrome (can be transection or caused by tumor)

Question 36

hemisection of the corticospinal tract will cause

Answer 36

ipsilateral spastic paralysis that begins at the level of transection and affects every level below that

Question 37

hemisection of the DC/ML tract will cause

Answer 37

ipsilateral deficit of touch, proprioception, and sensation that begins at the level of transection and affects every level below that

Question 38

hemisection of the spinothalamic tract will cause

Answer 38

**contralateral** deficit of pain and temperature sensation that begins a couple levels **below** transection and affects every level below that

Question 39

damage to the ventral horn of the spinal cord will damage what pathway?

Answer 39

damage the alpha motor neurons (LMN) for the corticospinal pathway (would see ipsilateral flaccid paralysis following a myotome) **gray matter**

Question 40

damage to the dorsal horn of the spinal cord will damage what pathway?

Answer 40

damage to both DC/ML and spinothalamic pathways (dermatomal ipsilateral loss of both touch and pain/temperature information) **gray matter**

Question 41

damage to the fasciulus gracillis would result in

Answer 41

ipsilateral loss of touch and vibration sensation in the legs

Question 42

white matter damage to the cord would result in [...] pain and temperature loss

Answer 42

contralateral

Question 43

damage to the [...] produces deficits confined to a dermatomal level

Answer 43

gray matter

Question 44

damage to the [...] impedes information that is ascending/descending the cord and results in deficits at the level of damage and below

Answer 44

white matter

Question 45

carry somatosensory information about ipsilateral touch and proprioception

Answer 45

dorsal columns

Question 46

carries the axons of UMNs

Answer 46

corticospinal tract (damage to the white matter will always result in spastic paralysis)

Question 47

the first order neuron of the spinothalamic tract lies in the

Answer 47

dorsal root ganglion

Question 48

the cell bodies that give rise to the axons in the spinothalamic tract reside in the

Answer 48

contralateral dorsal horn of the spinal cord

Question 49

the cell bodes that give rise to the lateral corticospinal tract are located in the

Answer 49

contralateral motor cortex

Question 50

the cell body of the UMN lives in the

Answer 50

contralateral motor cortex

Question 51

damage to the DC/ML will result in [...] deficit

Answer 51

ipsilateral

Question 52

damage to the spinothalamic tract will result in [...] deficit

Answer 52

contralateral

Question 53

why is the sensory deficit level for pain and temperature loss lower than the affected level?

Answer 53

sensory neurons initially ascend ipsilaterally for a couple of levels, then dessucate and ascend contralaterally

Question 54

how would a mid-thoracic lesion affect bladder function?

Answer 54

loss of UMN pathway of voluntary control SNS and PSNS still intact, but loss of voluntary control would cause a hyperreflexic, spastic bladder with urge frequency and incontinence

Question 55

pain and temperature afferents ascend [...] for one to two levels (in Lissauers tract), then synapse in the [...] dorsal horn (substantia gelantinosa)

Answer 55

ipsilateral ipsilateral (then second order neuron dessucates and ascends in contralateral ALS)

Question 56

damage to the [...] would produce ipsilateral flaccid paralysis in a dermatomal pattern

Answer 56

anterior horn

Question 57

the spinothalamic tract dessucated in the [...]

Answer 57

anterior white commissure

Question 58

syrinx can cause

Answer 58

central cord syndrome

Question 59

damage to [...] results in hyperreflexive spastic bladder

Answer 59

axons descending from pons micturition centers

Question 60

overflow incontinence results from damage to [...] in the sacral cord

Answer 60

parasympathetic preganglionic neurons