Spinal Cord Syndromes B&B Flashcards
what type of virus is polio, and to which part of the spinal cord does it cause destruction?
ssRNA virus
destruction of anterior horn —> LMN lesion —> flaccid paralysis
unvaccinated child with febrile illness presenting with neuro symptoms 4-5 days later as weakness preferentially in legs>arms and flaccid muscle tone
what are you thinking
polio: ssRNA virus, destruction of anterior horn (LMN) —> flaccid paralysis
Werdnig-Hoffman Disease
spinal muscle atrophy disease presenting with hypotonia/weakness in newborn (“floppy baby”) and tongue fasciculations
genetic condition with similar lesion to polio (anterior horn - LMN lesion), death within a few months
genetic spinal muscle atrophy disease presenting with hypotonia/weakness in newborn (“floppy baby”) and tongue fasciculations
Werdnig-Hoffman Disease
similar lesion to polio (anterior horn - LMN lesion), death within a few months
polio vs Werdnig-Hoffman Disease
polio: ssRNA virus, destruction of anterior horn —> LMN lesion —> flaccid paralysis
Werdnig-Hoffman Disease: genetic spinal muscle atrophy disease presenting with hypotonia/weakness in newborn (“floppy baby”) and tongue fasciculations, similar lesion to polio (anterior horn - LMN lesion), death within a few months
how does multiple sclerosis affect the spinal cord?
random, asymmetrical lesions of cervical white matter (demyelinating disease)
relapsing, remitting pattern, most often affects women
how does amyotrophic lateral sclerosis (ALS) affect the spinal cord? (aka Lou Gehrig’s disease)
combined UMN and LMN disease of unknown cause - lesions of anterior horns (LMN) and lateral corticospinal/corticobulbar tracts (UMN) - degeneration, but NOT demyelination
upper symptoms: spasticity, hyperreflexia
lower symptoms: wasting, fasciculations
no sensory symptoms
describe the symptoms of amyotrophic lateral sclerosis (ALS, aka Lou Gehrig’s disease)
combined UMN and LMN disease of unknown cause - lesions of anterior horns (LMN) and lateral corticospinal tracts (UMN)
upper symptoms: spasticity, hyperreflexia
lower symptoms: wasting, fasciculations
cranial nerves may be involved —> dysphagia (may lead to need for feeding tube)
no sensory symptoms
initial symptoms usually in limbs, asymmetric distribution
describe the prognosis of amyotrophic lateral sclerosis (ALS). what is the most common cause of death in patients with ALS?
ALS: combined UMN and LMN disease of unknown cause - lesions of anterior horns (LMN) and lateral corticospinal tracts (UMN)
most common 40-60yo, fatal 3-5 years most commonly by aspiration pneumonia (respiratory dysfunction)
what are the only 2 FDA approved drug for amyotrophic lateral sclerosis (ALS)?
ALS: combined UMN and LMN disease of unknown cause - lesions of anterior horns (LMN) and lateral corticospinal tracts (UMN)
- riluzole: decreases glutamate release from neurons, but only increases survival by a few months
- edaravone: free-radical scavenger, prevents functional deterioration
what is the cause of familial amyotrophic lateral sclerosis (ALS)?
ALS: combined UMN and LMN disease of unknown cause - lesions of anterior horns (LMN) and lateral corticospinal tracts (UMN)
familial ALS - autosomal dominant, due to zinc copper superoxide dismutase deficiency, SOD1 (free radical scavenger)
Pt is a 50yo M presenting with slowly worsening arm weakness and dysphagia to solids and liquids. On PE, some muscles appear flaccid while others appear spastic. However, sensation is intact. What is the diagnosis?
amyotrophic lateral sclerosis (ALS): combined UMN and LMN disease of unknown cause - lesions of anterior horns (LMN) and lateral corticospinal tracts (UMN)
upper symptoms: spasticity, hyperreflexia
lower symptoms: wasting, fasciculations
no sensory symptoms
what occurs in ASA occlusion?
anterior spinal artery occlusion = stroke of the spinal cord —> loss of all but posterior columns (these have separate blood supply)
acute onset (stroke) of flaccid or spastic bilateral paralysis (loss of LMN) below the lesion
vibration and proprioception remain intact (posterior columns)
what type of nerve function remains INTACT following ASA occlusion?
anterior spinal artery occlusion = stroke of the spinal cord —> loss of all but posterior columns (these have separate blood supply)
acute onset (stroke) of flaccid or spastic bilateral paralysis (loss of LMN) below the lesion
vibration and proprioception remain intact (posterior columns)
Pt presents to ED with acute onset of flaccid bilateral paralysis. Vibration and proprioception remain intact. What is the most likely cause?
anterior spinal artery (ASA) occlusion = stroke of the spinal cord —> loss of all but posterior columns (these have separate blood supply)
acute onset (stroke) of flaccid or spastic bilateral paralysis (loss of LMN) below the lesion
vibration and proprioception remain intact (posterior columns)
what is the cause of tabes dorsalis?
tertiary syphilis —> demyelination of the posterior columns of spinal cord + loss of dorsal roots
ataxia (loss of posterior column) + loss of reflexes (dorsal roots)
motor function is not affected
demyelination of the posterior columns of the spinal cord + loss of dorsal roots caused by tertiary syphilis
tabes dorsalis: ataxia (loss of posterior column) + loss of reflexes (dorsal roots)
motor function is not affected
Pt is a 37yo F with PMH of STD presenting with difficulty walking and fleeting, recurrent shooting pains in the legs. PE reveals a wide-based gait, loss of ankle and knee reflexes, positive Romberg sign, and Argyll Robertson pupils. However, strength in arms and legs is 5/5. What is the most likely cause?
tabes dorsalis: tertiary syphilis —> demyelination of the posterior columns of spinal cord + loss of dorsal roots
ataxia (loss of posterior column) + loss of reflexes (dorsal roots)
motor function is not affected
+Romberg = no proprioception
Argyll Robertson pupils: don’t react to light but can follow finger
syringomyelia
fluid-filled space in spinal canal, which compresses/damages spinothalamic nerves crossing through the center —> bilateral loss of pain/temp (only at the level of the syrinx)
can expand to anterior horn (LMN), lateral (sympathetics —> Horner’s), and can cause kyphoscoliosis (spine curve)
usually C8-T1 (arms/hands)
which nerves of the spinal cord are primarily involved in syringomyelia?
fluid-filled space in spinal canal, which compresses/damages spinothalamic nerves crossing through the center —> bilateral loss of pain/temp (only at the level of the syrinx)
can expand to anterior horn (LMN), lateral (sympathetics —> Horner’s), and can cause kyphoscoliosis (spine curve)
usually C8-T1 (arms/hands)
what segment of the spinal cord is most often involved in syringomyelia?
fluid-filled space in spinal canal, which compresses/damages spinothalamic nerves crossing through the center —> bilateral loss of pain/temp (only at the level of the syrinx)
can expand to anterior horn (LMN), lateral (sympathetics —> Horner’s), and can cause kyphoscoliosis (spine curve)
usually C8-T1 (arms/hands)
with what congenital malformations is syringomyelia strongly associated?
Chiari malformations: lower part of brain presses on and through an opening in the base of the skull and cerebellum into the spinal canal
fluid-filled space in spinal canal, which compresses/damages spinothalamic nerves crossing through the center —> bilateral loss of pain/temp
usually C8-T1 (arms/hands)
Pt is presenting to their GP with complaint of numbness in their arms and hands. PMH is significant for a spinal cord injury 5y ago. They have cuts and burns on their hands that they report they did not feel. PE reveals loss of pinprick and temp in back, shoulders, and arms. What is the most likely diagnosis?
syringomyelia: fluid-filled space in spinal canal, which compresses/damages spinothalamic nerves crossing through the center —> bilateral loss of pain/temp (only at level of syrinx)
can expand to anterior horn (LMN), lateral (sympathetics —> Horner’s), and can cause kyphoscoliosis (spine curve)
usually C8-T1 (arms/hands)
what is the cause of subacute combined demyelination (SCD)?
B12 deficiency
causes demyelination of the posterior columns (vibr/proprio) + loss of lateral motor tracts
—> slowly progressive weakness + ataxia
demyelination of the posterior spinal columns + loss of lateral motor tracts caused by B12 deficiency
subacute combined demyelination (SCD): causes demyelination of the posterior columns (vibr/proprio) + loss of lateral motor tracts
—> slowly progressive weakness + ataxia
which spinal tracts are affected by subacute combined demyelination (SCD)?
B12 deficiency causes demyelination of the posterior columns (vibr/proprio) + loss of lateral motor tracts
—> slowly progressive weakness + ataxia
Pt presents to their GP with complaint of trouble walking and spastic paresis in their legs that has slowly gotten worse. PE reveals a positive Romberg sign, lower extremity hyperreflexia, and a positive Babinski sign. What is the most likely diagnosis?
subacute combined demyelination (SCD): B12 deficiency causes demyelination of the posterior columns (vibr/proprio) + loss of lateral motor tracts
—> slowly progressive weakness + ataxia
Brown-Sequard Syndrome
loss of half of spinal cord due to trauma (gunshot) or tumor, symptoms below lesion:
—> loss of pain/temp on contralateral side (cannot cross)
—> loss of position/vibration on ipsilateral side (cannot ascend)
—> loss of motor on ipsilateral side that presents with LMN symptoms at the level of lesion, but UMN below the level of lesion
how are the spinal column tracts affected by Brown-Sequard Syndrome? (3)
loss of half of spinal cord due to trauma (gunshot) or tumor, symptoms below lesion:
- loss of pain/temp on contralateral side (cannot cross)
- loss of position/vibration on ipsilateral side (cannot ascend)
- loss of motor on ipsilateral side that presents with LMN symptoms at the level of lesion, but UMN below the level of lesion
describe how motor innervation is disrupted at the level of lesion and below the level of lesion in Brown-Sequard syndrome
loss of half of spinal cord due to trauma (gunshot) or tumor
—> loss of pain/temp on contralateral side (cannot cross)
—> loss of position/vibration on ipsilateral side (cannot ascend)
—> loss of motor on ipsilateral side that presents with LMN symptoms at the level of lesion, but UMN below the level of lesion
Pt presents to the ED following gunshot wound and it is determined he has Brown-Sequard syndrome. If weakness is felt on the left side of the body, which side of the spinal cord is lesioned?
loss of half of spinal cord due to trauma (gunshot) or tumor
—> loss of pain/temp on contralateral side below lesion (cannot cross)
—> loss of position/vibration on ipsilateral side below lesion (cannot ascend)
—> loss of motor on ipsilateral side that presents with LMN symptoms at the level of lesion, but UMN below the level of lesion
so, weak side = side with lesion
what are 3 potential causes of cauda equina syndrome?
aka compression of cauda equina
- massive disk rupture
- trauma
- tumor
how does cauda equina syndrome present?
aka compression of cauda equina
presents with severe low back pain, “saddle anesthesia” (numb over butt and posterior inner thighs), loss of anocutaneous reflex, bowel/bladder dysfunction
normal Babinski sign bc cauda equina is technically peripheral nerves —> LMN findings (not UMN)
describe the common presentations of multiple sclerosis (4)
- optic neuritis: unilateral blurred vision, eye pain, color desaturation
- transverse myelitis: weakness, numbness, urinary difficulty
- cerebellar: ataxia, dysmetria, nystagmus, scanning speech
- brainstem: diplopia, facial weakness/numbness, hearing loss
symptoms may be worse with heat (Uhtoff’s phenomenon), shooting pains with neck flexion (Lhermitte’s sign), tonic spasms throughout the day
Pt presents to your neurology clinic complaining of new onset of recurrent brief spasms throughout the day. They also report shooting pain when flexing their neck forward. By mid-afternoon, they feel exhausted despite plenty of sleep. They state the symptoms have been worse on hot days. What are you concerned about, and what other clinical findings are you on the lookout for? (4)
multiple sclerosis
- optic neuritis: unilateral blurred vision, eye pain, color desaturation
- transverse myelitis: weakness, numbness, urinary difficulty
- cerebellar: ataxia, dysmetria, nystagmus, scanning speech
- brainstem: diplopia, facial weakness/numbness, hearing loss
symptoms may be worse with heat (Uhtoff’s phenomenon), shooting pains with neck flexion (Lhermitte’s sign), tonic spasms throughout the day
what are the 4 subtypes of multiple sclerosis?
- relapsing-remitting
- relapsing-remitting followed by secondary-progressive
- progressive-relapsing
- primary-progressive (linear increase in symptoms)
describe the [hypothesis of] pathophysiology of multiple sclerosis
“outside-in hypothesis”: auto reactive T cells cross into CNS, trigger immune-mediated destruction of myelin
biopsy shows white matter plaques
what does biopsy and histology show, respectively, in multiple sclerosis?
biopsy: white matter plaques
histology: perivascular lymphocytes in active MS plaques
how is multiple sclerosis diagnosed (aside from clinical presentation/ history)?
contrast enhanced MRI: distinctive lesion pattern, enhancing lesions = recent/active, 3+ lesions = 80% relapse risk
CSF tap: presence of oligoclonal bands (OCB) doubles attack risk
serum studies: evaluate for mimicking disorders (of which there are many!)
how are acute multiple sclerosis relapses typically treated? (4)
- high dose IV steroids: methylprednisolone IV for 5 days
- intramuscular ACTH
- IV immunoglobin
- plasma exchange
these do not prevent future attacks or disease progression, only treat current symptoms
what is the mechanism and clinical use of natalizumab?
infusion disease-modifying therapy for multiple sclerosis (very effective!!)
mAb against alpha-4 integrin, preventing its interaction with VCAM-1 and subsequent T-cells from entering CNS
note: progressive multifocal leukoencephalopathy (PML) is rare but devastating side effect
Acute Disseminated Encephalomyelitis (ADEM)
often a monophasic post-viral demyelinating disease, treated with steroids
mimics MS, could be first (presenting) attack of multiple sclerosis
Neuromyelitis optica spectrum disorder (NMOSD)
Recurrent episodes of optic neuritis and/or transverse myelitis
labs show specific anti-aquaporin 4 antibody
can mimic multiple sclerosis
