Spinal cord lesions Flashcards
Where does poliomyelitis affect the spinal cord?
Destruction of anterior horn
Where does Werdnig-Hoffman disease affect the spinal cord?
Spinal Muscular Atrophy - destruction of anterior horn.
What are the characteristics of poliomyeltis and Werdnig Hoffman disease?
LMN lesions only due to destruction of anterior horn.
What causes poliomyelitis?
Poliovirus (fecal oral).
Where does poliomyelitis replicate?
Oropharynx and small intestine, then spreads via bloodstream to CNS.
What are the lab findings associated with poliomyelitis?
CSF with incr WBCs and slight icnr of protein w/ no change in glucose. Virus recovered from stool or throat.
What is the pathogenesis of Werdnig Hoffmans?
Congenital deterioration of anterior horns of spinal cord –> LMN lesion. Floppy baby, hypotonia, tongue fasciulations. Median age of death 7 months. AR inheritance.
Where does MS affect the spinal cord?
Demyelination sort of randomly; mostly affects white matter of cervical region.
Where does amyotrophic lateral sclerosis affect the spinal cord?
Lateral corticospinal tracts/anterior horns.
What is the presentation of ALS?
Combined UMN and LMN deficits with no sensory or oculomotor deficits. Both UMN and LMN signs.
Commonly presents as fasciculations with eventual atrophy and weakness of hands.
What enzyme deficiency can cause ALS?
superoxide dismutase 1.
What is the medication that is helpful?
RiLOUzole. (Lou Gherig). Glumatate antagonist. Mostly increases survival by decreasing presynaptic glutamate release.
What does occlusion of the anterior spinal artery cause?
2:00-10:00 of the spinal cord is knocked out. Spares dorsal columns and lissauer tract.
Where is the watershed area vulnerable to anterior spinal artery infarct?
Upper thoracic above T8. Below T8, artery of adamkiewicz supplies ASA territory.
What causes tabes dorsalis?
Tertiary syphilis. Degeneration/demyelination of dorsal columns and roots.
What are the sx of tabes dorsalis?
Impaird sensation and proprioception, progressive sensory ataxia, inability to sense or feel the legs, poor coordination.
What are findings are associated with tabes dorsalis?
Charcot joint, shooting pain, Argyl–Robertson pupils.
What will exam findings of tabes dorsal be?
Absence of DTRs and +romberg sign.
What will exam findings of tabes dorsal be?
Absence of DTRs and +romberg sign.
What is syringomelia?
Syrinx (central canal) expands and damages anterior white commissure of spinothalamic tract (2nd order neurons).
What are the sx of syringomelia?
Bilateral loss of pain and temperature sensation (usually C8-T1) in cape-like distribution.
What congential condition is syringomelia associated with?
Chiari I malformation.
How does B12 deficiency affect the spinal cord?
Subacute combined degeneration; demyelination of dorsal columns, lateral corticospinal tracts, and spinocerebellar tractsl ataxic gait, paresthesia, impaired position and vibration sense.
What does hemisection of spinal cord cause?
Brown-Sequard syndrome:
Below Lesion:
- Ipsilateral UMN signs below level of lesion.
- Ipsilateral loss of tactile/vibration/proprioception below level of lesion.
- Contralateral pain and temp loss below level of lesion.
At level of lesion:
- Ipsilateral loss of all sensation at level of lesion.
- Ipsilateral LMN signs.
What happens w/ hemisection above T1?
Horner syndrome due to loss of oculosympathetic pathway.
What congenital syndrome causes degeneration of multiple spinal cord tracts, presents w/ kyphoscoliosis, and is autosomal recessive?
Fredreich ataxia.
What is the pathogenesis of Fredreich ataxia?
Autosomal recessive trinucleotide repeat disorder (GAA) on Ch 9 in gene that encodes frataxin, an iron binding protein.
What sx are seen w/ Fredreich ataxia?
Loss of mitochondrial function.
Muscle weakness, loss of DTRs, dorsal columns.
Staggering gait, frequent falling, nystagmus, dysarthria.
Systemic:
DM, HCM, pes cavus, hammer toes. kyphscoliosis.
