129: Tracts of the spinal cord

Question 1

Main ascending tracts

Answer 1

spinothalamic and dorsal column

Question 2

main descending tracts

Answer 2

corticospinal tract and autonomic pathways ( bladder, bowel, sexual function)

Question 3

what does the dorsal column relay?

Answer 3

proprioception, light touch and vibration

Question 4

what does the lateral corticospinal tract relay?

Answer 4

motor

Question 5

what do the lateral spinalthalamic tracts relay?

Answer 5

pain and temperature

Question 6

in the dorsal column where do the fasciculus gracilis relay information from?

Answer 6

the upper limbs

Question 7

in the dorsal column where do the fasciculus cuneatus really information from?

Answer 7

the lower limbs

Question 8

where does the corticospinal tract decussate?

Answer 8

at the caudal medulla (ventral surface)

Question 9

where does the spinothalamic tract desucate?

Answer 9

at the level it enters the spine

Question 10

Where does the dorsal column decussate?

Answer 10

medulla nucleus

Question 11

definition: mylo

Answer 11

spinal cord

Question 12

definition: radiculo

Answer 12

nerve root

Question 13

definition: neuro

Answer 13

peripheral nerve

Question 14

definition: myo

Answer 14

muscle

Question 15

Pattern of weakness in upper motor neurone disease?

Answer 15

extensors weaker than flexors in the arms, flexers weaker than extensors in the legs

Question 16

where does the spinothalamic pathway synapse?

Answer 16

thalamus

Question 17

where does the dorsal column synapse?

Answer 17

thalamus

Question 18

where edoes the corticospinal tract synapse?

Answer 18

anterior horn of spinal cord with the motor neurones.

Question 19

recurrent inhibition is controlled by?

Answer 19

Renshaw cells - via glycine

Question 20

the inverse myotatic reflex is controlled by?

Answer 20

golgi tendon ( inhibits muscle contraction, drop heavy things)

Question 21

stretch of a muscle spindle activates which sensory neurone?

Answer 21

1a afferent (myotatic reflex)

Question 22

stretch of a golgi tendon activates which sensory neurone?

Answer 22

1b afferent

Question 23

what do gamma motor neurones do?

Answer 23

cause contraction of the spindle to regenerate tension

Question 24

what do alpha motor neurones do?

Answer 24

cause muscle contraction

Question 25

what does a lower motor neurone do?

Answer 25

innervate muscle

Question 26

what does an upper motor neurone do?

Answer 26

innervate lower motor neurons

Question 27

classic lower motor neurone lesion signs

Answer 27

hyporeflexia, fasiculations, muscle atrophy, denervation

Question 28

classic upper motor neurone signs

Answer 28

paralysis, babinski, tonus, spasticity, hyper reflexia (UMN dampen down reflex response).

Question 29

what is brown-sequad syndrome?

Answer 29

loss of one half of the spinal cord - ipsilateral proprioception and motor loss (dorsal and corticospinal cross at medulla), contralateral pain and temperature loss (cross at site of entry)