spinal cord lesions. consider drawing.

Question 1

Where is the lesion for poliomyelitis? What are the characteristics of this disease?

Answer 1

Affects the anterior horn LMNs. causes flaccid paralysis. also seen in spinal muscular atrophy.

Question 2

What is spinal muscular atrophy?

Answer 2

Just like poliomyelitis, spinal muscular atrophy causes destruction of the anterior horn LMNs and flaccid paralysis. muscle atrophy, and proximal more than distal weakness.

Question 3

Draw where you would expect a spinal cord lesion to be for MS. What kinds of effects?

Answer 3

see pg 467, but basically you should shade in white matter of the cervical region. this is an UPPER neuron disease. lesions are random and asymmetric. causes scanning speech, intention tremor, nystagmus

Question 4

What are the characteristics of ALS? What is NOT affected by ALS?

Answer 4

amyotrophic lateral sclerosis
combined UMN and LMN deficits w/o sensory, cognitive, or oculomotor deficits. Has both UMN and LMN signs. usually not pain.

Question 5

What is the most common presentation of ALS?

Answer 5

fasciculations with eventual atrophy and weakness of the hands
or, dysarthria first, dysphagia later, or foot drop/gait appearance.

Question 6

What is one cause of ALS?

Answer 6

mutations in superoxide dismutase 1.

Question 7

What is one treatment for ALS and how does it work?

Answer 7

riluzole modestly increases survival by decreasing presynaptic glutamate release.

Question 8

What pathology would be seen with complete occlusion of anterior spinal artery?

Answer 8

only the dorsal columns and lissauer’s tract are spared. (which seems to move connect sensory fibers in both up and down directions. this is why sensory levels may occasionally be seen below the level of the lesion- ie lesions are higher than you would expect based on the pain/temperature level).

Question 9

What is tabes dorsalis? Clinical findings? Exam findings?

Answer 9

caused by tertiary syphilis. results from degeneration/demyelination of dorsal columns and roots. loss of epicritics (proprioception, fine touch) and progressive sensory ataxia. exam will show abscence of DTRs and a positive Romberg

Question 10

With what other problems is tabes dorsalis associated?

Answer 10

Charcot joints (joints without sensation- can get very damaged because you can’t feel them), shooting pain, Argyll Robertson pupils (small irregular pupils that constrict to convergence but not to light)

Question 11

What spinal cord pathology is associated with vitamin B12 or vitamin E deficiency?

Answer 11

Subacute combined degeneration: demyelination of the dorsal columns, lateral corticospinal tracts, and spinocerebellar tracts. causes ataxic gait, paresthesia, impaired position and vibration sense.

Question 12

What is syringomyelia?

Answer 12

A common spinal cord lesion associated with Arnold-Chiari I malformation in which a patient has a cystic lesion in the spinal cord. As it expands, it can damage the anterior white commissure, causing loss of pain and temperature in a cape-like distribution. Usually seen in C8-T1.

Question 13

Describe polio process

Answer 13

fecal-oral poliovirus replicates in the oropharynx and small intestine, then spreads by the blood to the CNS. It destroys the LMN cells of the anterior horn

Question 14

What would the CSF findings be for someone with polio?

Answer 14

incr. WBC and slight incr. protein w/o a change in CSF glucose.

Question 15

Clinical manifestation of spinal muscular atrophy

Answer 15

congenital degeneration of anterior horn LMNs. leads to a floppy baby with marked hypotonia and tongue fasciculations. autosomal recessive.
infantile type causes death at 7 months

Question 16

Freidrich’s ataxia: genetic lesion and molecular consequence

Answer 16

autosomal recessive trinucleotide repeat disorder on chronosome 9. Frataxin is the protein product. leads to impaired mitochondrial function.

Question 17

What is the clinical consequence of Friedrich’s ataxia?

Answer 17

degeneration of multiple spinal cord tracts causing muscle weakness and loss of DTRs, vibratory sense, and proprioception. staggering gait, frequent falls, and hypertrophic cardiomyopathy
(also nystagmus, dysarthria, hammer toes, childhood kyphoscholiosis)

Question 18

What is Brown-Sequard syndrome?

Answer 18

hemisection of the spinal cord. Causes a band of numbness at the level of the lesion, ipsilateral loss of epicritics (fine touch, vibration, probprioception) 1-2 levels below the lesion, contralateral loss of pain and temperature. ipsilateral motor loss.
if lesion is above T1, pt may have Horner’s syndrome.