Neurology- Spinal cord lesions- Pathoma

Question 1

spinal cord tracts (list 4)

Answer 1

• spinothalamic (pain and temperature sensation)
• dorsal column- medial lemniscus (pressure, touch, vibration, and proprioception)
• lateral corticospinal (voluntary movement)
• hypothalamospinal (sympathetic input of the face)

Question 2

spinothalamic (pain and sensation)

first- order neuron

Answer 2

peripheral nerves to posterior horn; cell body in dorsal root ganglion

Question 3

spinothalamic (pain and sensation)

second- order neuron

Answer 3

arises from posterior horn, immediately crosses over in anterior white commmissure, and ascends via the spinothalamic tract to the thalamus

Question 4

spinothalamic (pain and sensation)

third- order neuron

Answer 4

thalamus to cortex

Question 5

Dorsal column- medial lemniscus (pressure, touch, vibration, and proprioception)
first- order neuron

Answer 5

peripheral nerves to medulla via dorsal column; cell body is in dorsal root ganglion

Question 6

Dorsal column- medial lemniscus (pressure, touch, vibration, and proprioception)
second- order neuron

Answer 6

arises from medulla, crosses over, asvends via the medial lemniscus to thalamus

Question 7

Dorsal column- medial lemniscus (pressure, touch, vibration, and proprioception)
third- order neuron

Answer 7

thalamus to cortex

Question 8

Lateral corticospinal (voluntary movement) 
first- order neuron

Answer 8

pyramidal neurons in cortex descend, cross over in medullary pyramids, and synapse on the anterior motor horn of the neuron (upper motor neuron)

Question 9

Lateral corticospinal (voluntary movement) 
second- order neuron

Answer 9

arises from the anterior motor horn and synapses on muscle (lower motor neuron)

Question 10

Lateral corticospinal (voluntary movement) 
third order neuron

Answer 10

haha jk. there are only 2 neurons in this tract

Question 11

Hypothalamospinal (sympathetic input of the face)

first- order neuron

Answer 11

arises from the hypothalamus and synapses on the lateral horn at T1

Question 12

Hypothalamospinal (sympathetic input of the face)

second- order neuron

Answer 12

arises from the lateral horn at T1 and synapses on the superior cervical ganglion (sympathetic)

Question 13

Hypothalamospinal (sympathetic input of the face)

third- order neuron

Answer 13

superior cervical ganglion to eyelids, pupil, skin of face

Question 14

Syringomyelia- what is it?

Answer 14

cystic spinal cord degeneration secondary to trauma or Arnold- Chiari malformation

Question 15

Syringomyelia- where does it happen?

Answer 15

Usually C8-T1
Presents as sensory loss of pain and temperature. Fine touch and position sense are spared in the upper extremities (cape- like distribution) due to involvement of the anterior white commissure of the apinothalamic tract. Dorsal column is spared

Question 16

Syringomyelia- complications

Answer 16

Other spinal tracts, aside from the spinothalamic tract, become involved when the syrinx expands. When LMN of anterior horn is damaged, the patient may experience muscle atrophy, weakness, decreased muscle tone, impaired reflexes.
When the lateral horn of the hypothalamospinal tract is damaged, there is Horner Syndrome

Question 17

Horner Syndrome

Answer 17

ptosis, miosis, anhidrosis due to disruption of the hypothalamospinal tract

Question 18

Poliomyelitis- where does it occur?

Answer 18

anterior motor horn due to poliovirus infection (feco-oral transmission followed by hematogenous spread to the spine)

Question 19

Poliomyelitis- how does it present?

Answer 19

lower motor neuron signs- flaccid paralysis with muscle atrophy, fasciculations, weakness with decreased muscle tone, impaired reflexes

Question 20

Werdnig-Hoffman- what is the pattern of inheritance?

Answer 20

autosomal recessive degeneration of the anterior motor horn

Question 21

Werdnig- Hoffman- how does it present?

Answer 21

“floppy baby” death by age 2