Spinal Cord Disease

Question 1

spinal muscular atrophy

Answer 1

• cause = degeneration of anterior horn cells b/c of a deletion on chrom 5q that encodes for “survival motor neuron”
• NO UMN signs
• more common types = werdnig-hoffman disease and kugelberg-welander disease
• usually seen in kids but can happen in adults

Question 2

werdnig-hoffman disease

Answer 2

• evident in first few weeks of life
• commonly called floppy baby syndrome
• decreased intrauterine movement, progressive symmetric weakness, weak cry, swallowing difficulty, respiratory failure
• death in a few years

Question 3

kugelberg-welander disease

Answer 3

• onset in childhood
• generalized weakness
• oropharyngeal mm. are spared
• longer life span than werdnig-hoffman babies

Question 4

How do you dx werdnig-hoffman or kugelberg-welander? tx?

Answer 4

• H&P
• m. biopsy: fiber type grouping, group atrophy
• electromyography
• tx symptoms

Question 5

amyotrophic lateral sclerosis: result of disease and possible causes

Answer 5

• degeneration of corticospinal tract and anterior horn cells
• most commonly sporadic but 10% are familial
• Chrom 20 autosomal dominant - VAPB vesicle trafficking protein could affect severity and form of ALS
• some cases caused by mutation in superoxide dismutase type 1 resulting in gain of function; others due to alteration in VEGF
• juvenile onset ALS = flaw in protein senataxin
• upiquilin 2 - gene UBQLN2; regulates protein degredation pathways; results in accumulation of proteins and cell death

Question 6

ALS: risk factors, onset, what is spared

Answer 6

• risk factors = age, male sex, being thinner
• onset: mid to late adulthood
• may begin asymmetrically and there are no sensory findings
• spares extraocular and urinary sphincter mm. –> thought that the nucleus has a property protecting it

Question 7

ALS possible presentations: LMN and UMN findings and symptoms associated w/ each; bulbar palsy; combo of all

Answer 7

• LMN: b/c of anterior horn being affected; causes m. atrophy/weakness, dysphagia, weight loss, cramps, fasciculations
• UMN: b/c of corticospinal tract degredation; causes hyperreflexia, spasticity, weakness, gait difficulty, Babinski sign
• Bulbar palsy: primarily affects cranial anterior horn cells; causes dysphagia, aspiration (pneumonia), hoarseness; pts w/ this presentation will die in a few years; can prolong life w/ ventilator, PEG tube

Question 8

ddx for ALS

Answer 8

1. cervical spondylosis: but would also have numbness and no bulbar symptoms
2. syringomyelia
3. other myelopathies
4. Anti-GM1 antibody: causes LMN findings, rare but treatable

Question 9

how do you make a dx of ALS?

Answer 9

• H&P
• EMG
• MRI of spine

Question 10

ALS tx options

Answer 10

1. supportive: vaccinations, nutrition, etc.
2. symptomatic: spasticity meds like diazepam, baclofen, dantrolene
3. new medication = riluzole – only FDA approved drug for ALS; prolong life by 10-20%
4. experimental: add rasagiline to riluzole; genetic: VEGF gene or its protein injected into pt

Question 11

ALS prognosis

Answer 11

• pts dies from respiratory failure or infection
• dead w/in 5 years
• can prolong life w/ feeding tube and/or ventilator but it becomes a quality of life issue

Question 12

syringomyelia

Answer 12

• chronic progressive tubular cavitation of spinal cord
• develops after trauma, hematomyelia, cystic degeneration of a glioma, ischemia
• associated w/ Arnold-Chiari malformation

Question 13

hydromyelia

Answer 13

type of syringomyelia where there is a dilation of the central canal

Question 14

syringobulbia

Answer 14

term for a syringomyelia that occurs in the brainstem

Question 15

syringomyelia: clinical features

Answer 15

• most commonly in lower cervical cord
• dissociated sensory loss, cape distribution pain & temp loss, atrophy and weakness of hands, paraparesis, fasciculations, hyperreflexia, Babinski signs, bowel and bladder impairment, pain in neck and shoulders, scoliosis, Charcot joints

Question 16

syringomyelia ddx

Answer 16

• ALS
• MS
• spinal cord tumor
• cervical spondylosis

Question 17

how do you dx a syringomyelia?

Answer 17

• MRI is the best option

- myelogram if you can’t get an MRI

Question 18

syringomyelia tx?

Answer 18

• surgical
• radiation
• if it’s small enough it may be asymptomatic and you can just watch them

Question 19

subacute combined degeneration: causes

Answer 19

• result of a B12 deficiency; pernicious anemia = no intrinsic factor = no absorption of B12
• has CNS and PNS features
• myelin loss in posterior columns
• could have a normal CBC

Question 20

subacute combined degeneration: clinical features

Answer 20

• sensory ataxia: cerebellum not getting enough feedback
• paresthesias in the feet
• impaired vibration and position sense
• spasticity, hyperreflexia, Babinski signs = UMN findings

Question 21

subacute combined degeneration: diagnosis and treatment

Answer 21

• H&P
• B12 levels: homocysteine and methylmalonic acid levels
• B12 t be normalized w/ folic acid supplement
• CBC: megaloblastic, hyperchromic, and macrocytic changes
• Tx w/ IM B12: want to see the methylmalonic acid level come down; the shots will stop the process but not totally reverse the pathologic findings

Question 22

Arnold-Chiari Malformation: what it is and possible causes

Answer 22

• congenital anomaly
• downward elongation of the hindbrain into cervical column
• possible causes = cord fixation at the bottom, developmental arrest, overgrowth of neural tube
• associated w/ spina bifida, hydrocephalus, syringomyelia

Question 23

Arnold-Chiari Malformation: clinical features

Answer 23

• hydrocephalus in the first few years

- in adult onset: ataxia, weakness, nystagmus, myelopathic (UMN) signs

Question 24

Arnold-Chiari Malformation: dx and tx

Answer 24

• H&P and MRI for dx

- tx = surgery

Question 25

spina bifida: what it is, possible causes, high risk meds

Answer 25

- failure of closure of bony spine - most common at lumbosacral region but can occur anywhere along spine or cranium - genetic, environmental, and nutritional factors: folic acid, VANGL1 gene, MTHFR gene - folic acid antagonists: trimethoprim, phenytoin, carbamazepine, phenobarbital, triamterene, primidone - high risk if mom on seizure meds b/c they deplete folic acid

Question 26

types of spina bifida

Answer 26

1. occulta: vertebral arch didn't fuse; characteristic patch of hair 2. meningocele - meninges herniated through 3. myelomeningiocele: meninges + cord 4. dermal sinus: pit in the skin down through the failed arch closure to the cord

Question 27

spina bifida: clinical features

Answer 27

- asymptomatic - dermatological features: overgrowth of hair, sinus, nevus flammeus, pit, lipoma - neuro features: weakness, atrophy, gait disturbance, B&B symptoms, sensory loss, areflexia

Question 28

spina bifida: dx and ts

Answer 28

- dx by H&P, MRI, CT scan, plain x-rays - prevention tx: folic acid and vitamin A supplements for women of child bearing age - surgical tx can be an option for the more severe types

Question 29

Friedreich's Ataxia: what it is and causes

Answer 29

- very rare; familial and hereditary disease - localized to chrom 9 & 11; deficiency of functional frataxin (involved in mitochondrial homeostasis) - onset in the 1st-2nd decade - degeneration of posterior funiculi, lateral CST, spinocerebellar tracts, dorsal roots, and Clarke's column

Question 30

Friedreich's Ataxia: clinical features and tx

Answer 30

- areflexia - ataxia - loss of position sense - nystagmus - scoliosis - pes cavus - cardiomyopathy - interesting clinical features = + Babinski and areflexia b/c they are UMN and LMN signs together - symptomatic tx

Question 31

cervical spondylosis w/jj myelopathy

Answer 31

- progressive degenerative disc changes w/ bony changes causing pressure on cord resulting in ischemia to the cord - myelopathic findings - dx by H&P and MRI - tx can be surgical or conservative; the only tx for compression of spinal cord is surgery

Question 32

conus medullaris syndrome

Answer 32

- urinary and/or fecal incontinence - failure of erection and ejaculation - paralysis of pelvic floor - sensory loss - reflexes usually spared - often occurs w/ cauda equine syndrome

Question 33

brown-sequard syndrome

Answer 33

- hemisection of spinal cord - i/l PCML loss and weakness - c/l pain and temp loss - causes = trauma, radiation, or tumor

Question 34

anterior spinal artery syndrome

Answer 34

- caused by atherosclerosis or dissecting aneurysm resulting in occlusion of a. of Adamkiewicz - infarct of anterior 2/3 of spinal cord - clinical features: paralysis and dissociative sensory loss - PCML not affected

Question 35

posterior spinal artery syndrome

Answer 35

- rare - occludes both of the posterior spinal aa. - loss of vibration and position sense = PCML losses

Question 36

spinal shock

Answer 36

- abrupt; occurs after complete or incomplete spinal cord injury - complete paralysis, anesthesia, areflexia, and hypotonia - UMN signs will develop after a week (or 3-4 weeks for Jesper); + Babinski right away for UMN injuries

Question 37

chronic cord transection

Answer 37

- after spinal shock | - permanent motor, sensory and autonomic loss from that level down