Neuro 17.2: Spinal Cord Lesions Flashcards
1
Q
What is the mutation in Friedreich Ataxia?
A
unstable trinucleotide repeat (GAA) in the frataxin gene
2
Q
What is Friedreich Ataxia?
A
- a degenerative disorder of the cerebellum and spinal cord tracts
- *** “Friedreich is Fratastic (frataxin): he’s your favorite frat brother, always staggering and falling but has a sweet, big heart.”
3
Q
Where does sensory info for pain/temperature ascend?
A
in the spinothalamic tract
4
Q
Why does dysfunction of the frataxin gene cause Friedreich Ataxia to occur?
A
- normal = essential for mitochondrial iron regulation
- damage = increased risk of free radicals via the Fenton reaction –> free radical damage of neurons
5
Q
What is Riluzole? What is it for? How does it work?
A
- tx for ALS/Lou Gehrig disease
- decreases glutamate excitotoxicity (via unknown mech.)
- *** “For Lou Gehrig disease, give rilouzole”
6
Q
Dx?
- unstable trinucleotide repeat (GAA) in the frataxin gene
A
Friedreich Ataxia
7
Q
Where in the spinal cord is the the hypothalamic spinal tract found?
A
in the lateral horns
8
Q
What does syringomyelia arise in assoc. with?
A
- trauma
- Arnold-Chiari malformation
9
Q
Who classically gets Amyotrophic Lateral Sclerosis (ALS)?
A
middle-aged adults
10
Q
Where does sensory info for pain/temperature decussate?
A
at the anterior white commissure
11
Q
This is the name for the cystic degeneration of the spinal cord at the anterior white commissure.
A
syringomyelia
12
Q
Dx?
- a degenerative disorder of upper AND lower motor neurons (the corticospinal tract)
A
Amyotrophic Lateral Sclerosis (ALS)
13
Q
How is polio transmitted?
A
fecal oral
14
Q
Which spinal cord lesion presents with a “cape-like” distribution of symptoms?
A
syringomyelia
15
Q
O2- + superoxide dismutase = _______
A
H2O2
16
Q
What does a negative Babinkski sign look like?
A
downgoing toes
17
Q
What are the initial s/s of a poliovirus infection?
A
- fever
- sore throat
- ab pain
- nausea/vomiting
18
Q
How can Amyotrophic Lateral Sclerosis (ALS) be distinguished from syringomyelia?
A
there is NO sensory impairment in Amyotrophic Lateral Sclerosis (ALS)
19
Q
At what level of the spinal cord does syringomyelia classically occur?
A
C8-T1
20
Q
If a syringomyelia lesion expanded, it would knock out the anterior horns and then the ______ of the spinal cord.
A
lateral horns
21
Q
On which chromosome is the frataxin gene located?
A
chromosome 9
22
Q
What are the 3 classic findings of Horners syndrome?
A
ptosis, myosis, and anhydrosis
23
Q
Where does sensory info for pain/temperature synapse?
A
in the posterior horn of the spinal cord
24
Q
What is the prognosis for Werdnig-Hoffman disease?
A
death w/i a few years after birth (median = 7 mos)
25
What disease presents like poliovirus?
Werdnig-Hoffman disease
26
What is Amyotrophic Lateral Sclerosis (ALS)?
a degenerative disorder of upper AND lower motor neurons (the corticospinal tract)
27
Where in the body does poliovirus initially infect?
oropharynx and small bowel
28
Dx?
* a degenerative disorder of the cerebellum and spinal cord tracts
* ataxia
* loss of vibration sense
* loss of proprioception
* muscle weakness in lower extremities
* loss of DTRs
Friedreich Ataxia
29
How does poliomyelitis present?
* lower motor neuron signs:
* muscle weakness and atrophy
* decreased tone
* impaired reflexes
* flaccid paralysis
* negative Babinksi sign (downgoing toes)
30
What info. does the dorsal column of the spinal cord carry?
fine touch/position sense
31
If a syringomyelia lesion expanded, it would first knock out the _____ of the spinal cord.
anterior horns
32
What runs thru the lateral horn of the spinal cord?
the hypothalamal spinal tract- sympathetic input to the face
33
Upper motor neurons start in the cortex and first synapse in the anterior horn of the spinal cord. Then, the lower motor neuron continues on to the \_\_\_\_\_\_\_.
muscle
34
What are the upper motor neuron (UMN) dysfunction signs?
* spastic paralysis
* hyperreflexia
* increased muscle tone
* positive Babinski sign (= upward going toes)
35
How is Werdnig-Hoffman disease transmitted?
auto. recessive inheritance
36
What are the clinical s/s associated with loss of the hypothalamal spinal tract at T1?
* ptosis, myosis, and anhydrosis (Horner's syndrome)
37
What are the sensory findings in syringomyelia?
* **loss of pain and temp.** sensation in the upper extremities
* \*\*\*fine touch, position sense **in tact**
38
How does one get Friedreich Ataxia?
it's auto. recessive
39
What is poliomyelitis?
damage to the anterior motor horn due to poliovirus infection
40
Upper or lower motor neuron defect?
* muscle weakness and atrophy
* decreased tone
* impaired reflexes
* flaccid paralysis
* negative Babinksi sign
lower motor neuron
41
What will the CSF findings be in polio?
* increased WBCs
* slightly increased protein
* normal glucose
42
What is the function of the frataxin gene?
it's essential for mitochondrial iron regulation
43
O2- --\> H2O2 via?
superoxide dismutase (SOD)
44
What are the signs of lower motor neuron dysfunction?
* muscle weakness and atrophy
* decreased tone
* impaired reflexes
* flaccid paralysis
* negative Babinksi sign = downgoing toes
45
Where does sensory info for pain/temperature synapse in the brain?
the thalamus --\> cortex
46
Does polio present with symmetric or asymmetric weakness? What about Werdnig-Hoffmann disease?
* polio = asymmetric
* Werdnig-Hoffmann = symmetric
47
What familial mutation is known to cause Amyotrophic Lateral Sclerosis (ALS)?
zinc-copper superoxide dismutase mutation
48
In the hypothalamic spinal tract, a nerve arising in the ______ synapses on the lateral horn at T1.
hypothalamus
49
In the hypothalamic spinal tract, a nerve arising in the hypothalamus synapses on the _______ at T1.
lateral horn
50
Do ALS pts have bowel/bladder deficits?
nope
51
Where is the cell body located for pain/temperature?
in the sensory ganglion outside the spinal cord
52
How many different nerves are used to transmit pain/temperature info from the periphery to the brain?
3
53
This gene is essential for mitochondrial iron regulation.
the frataxin gene
54
How is Amyotrophic Lateral Sclerosis (ALS) transmitted?
* most = sporadic genetic mutations
* some = familial zinc-copper superoxide dismutase mutation
55
What other pathology is Friedreich Ataxia associated with?
* hypertrophic cardiomyopathy
* diabetes mellitus
* hammer toes
56
Upper motor neurons start in the cortex and first synapse in the \_\_\_\_\_\_\_.
anterior horn of the spinal cord
57
Ataxia + multiple spinal cord tract dysfunction = ?
Friedreich Ataxia
58
What is the function of superoxide dismutase (SOD)?
removal of free radicals
59
How does poliovirus get to the CNS?
hematogenous spread
60
What occurs in the posterior horn of the spinal cord?
pain/temperature sensory info synapses here
61
What info. is transmitted in the anterior horn of the spinal cord?
motor neurons
62
Dx?
* an inherited degeneration of the anterior motor horn
Werdnig-Hoffman disease
63
Why is syringomyelia?
a cystic degeneration of the spinal cord at the anterior white commissure
64
In the hypothalamal spinal tract, a nerve arising in the hypothalamus synapses on the lateral horn at \_\_\_\_\_.
T1
65
Is there loss of pain/temp sensation in ALS or syringomyelia?
syringomyelia
66
Where in the spinal cord does syringomyelia classically occur?
in the anterior white commissure
67
How does Werdnig-Hoffman disease present?
* a floppy baby
* tongue fasciculations
* s/s similar to polio but will have **SYMMETRIC WEAKNESS**
68
Upper or Lower Motor Neuron dysfunction signs?
* spastic paralysis
* hyperretlexia
* increased muscle tone
* positive Babinski sign
Upper motor neuron
69
Dx?
* damage to the anterior motor horn due to poliovirus infection
* lower motor neuron signs
poliomyelitis
70
What is the result if the anterior white commissure of the spinal cord is lesioned?
bilateral loss of pain and temperature sensation
71
What neuro. disease is hypertrophic cardiomyopathy assoc. with?
Friedreich Ataxia
72
When does Friedreich Ataxia present? How?
* in early childhood
* kyphoscoliosis
73
What info does the hypothalamic spinal tract carry?
sympathetic input to the face
74
How does Friedreich Ataxia present?
* ataxia
* loss of vibration sense
* loss of proprioception
* muscle weakness in lower extremities
* loss of DTRs
75
Does a syringomyelia usually affect the upper or lower limbs? Why?
* upper
* because they usu. occur at C8-T1
76
What is an early sign of Amyotrophic Lateral Sclerosis (ALS)?
* atrophy
* hand weakness
77
What occurs in the at the anterior white commissure of the spinal cord?
sensory info for pain/temperature decussates
78
What does a zinc-copper superoxide dismutase mutation cause?
Amyotrophic Lateral Sclerosis (ALS)
79
Does Amyotrophic Lateral Sclerosis (ALS) present with upper or lower motor neuron dysfunction signs? Why?
* Both
* Anterior motor horn involvement = LMN signs
* Lateral corticospinal tract involvement = UMN signs
80
What is the tx for ALS? How does it work?
* riluzole
* decreases glutamate excitotoxicity (via unclear mech.)
* \*\*\* "For **Lou** Gehrig disease, give ri**lou**zole"
