Wahba Part 2 - Myelopathy

Question 1

Pathogenesis of Lambert-Eaton

Answer 1

Dysfunction of presynaptic Ach release 2/2 Abs against P/Q type voltage-gated Ca channels

Question 2

Symptoms of Lambert-Eaton

Answer 2

Generalized fatigue+weakness, myalgia, muscle tenderness, stiffness, strength improves w/ exercise, metallic taste in mouth and dryness, orthostasis, constipation, impotence, DTR absent/diminished

Question 3

Epidemiology of Lambert-Eaton

Answer 3

60% have small cell carcinoma, 90% have Abs against P/Q type VGCC, 50% have Abs against N type VGCC

Question 4

How to dx L-E

Answer 4

Compound muscle action potential

Question 5

Treatment of L-E

Answer 5

1st evaluate for malignancy, guanidine hydrochloride inhibits mitochondrial Ca uptake (causes myelosuppresion)

Question 6

Location of lesion of cauda equina syndrome

Answer 6

Affects nerve roots between T10, lower border of L1

Question 7

Signs and symptoms of cauda equina syndrome

Answer 7

Root compression, paraplegia, BL absence of ankle reflex, urinary retention, post-void residual incontinence, decreased anal tone and fecal incontinence, sexual dysfunction, saddle anesthesia

Question 8

Etiologies of cauda equina syndrome

Answer 8

Traction and pelvic fractures following gunshot injuries, MVA, and falls

Question 9

Imaging in cauda equina syndrome

Answer 9

CT, MRI

Question 10

Treatment of cauda equina syndrome

Answer 10

Surgical decompression, spinal nerve reconstruction, repair of ventral nerves and nerve transfer

Question 11

When to MRI cauda equina syndrome

Answer 11

Weakness+reflexes+radiculopathy signs

Question 12

Red flags of myelopathy

Answer 12

Loss of weight+night sweats+endemic areas+TTP on spine

Question 13

What to do if no red flags

Answer 13

Give muscle relaxer/NSAID

Question 14

Features of acute myelopathy

Answer 14

Acute onset of weakness+sensory loss+ANS dysfunction (urinary retention), absence of other cortical findings

Question 15

CSF findings in acute myelopathy

Answer 15

Mild-moderate lymphocytic pleocytosis, increase protein, normally or mildly decreased glucose

Question 16

Differential for myelopathy

Answer 16

Vascular - SC infarction, bacterial/fungal/parasitic/viral infections, Autoimmune - SLE, MS, Structural - compression, nucleus pulposus herniation

Question 17

S and S of myelopathy

Answer 17

Weakness, sensory loss @ level, autonomic dysfunction, loss of anal sphinter tone+cremasteric reflex+anal wink+bulbocavernosus response, urinary retention, bowel dysfunction

Question 18

Features of transverse myelitis

Answer 18

Complete axial plane transection of cord; all sensory/motor loss below the lesion; viruses most likely etiology

Question 19

Features of partial myelitis

Answer 19

Brown Sequard - ipsilateral UMN signs, ipsilateral loss of tactile, vibration, propioception sense, C/L loss of pain and temp (pinprick demarks 1-2 levels below lesion), LMN signs at level of lesion, Horner’s (above T1)

Question 20

Partial myelitis - acute vs chronic?

Answer 20

Acute has increased tone and reflexes; chronic has spasticity w/ pathologic reflexes

Question 21

Etiology of poliomyelitis

Answer 21

Poliovirus, West Nile, Enterovirus

Question 22

Features of poliomyelitis

Answer 22

Weakness of LMN, occurs w/in days of acute viral syndrome including meningitis; weakness is acute, asymmetric, mostly in legs; bladder dysfunction; loss of tone+reflexes; sensory spared

Question 23

CSF findings and Dx of polio

Answer 23

mild-mod lymphocytic pleocytosis, increased protein, increased IgG synthesis, viral PCR and Ab titers; also get MRI spine (swollen+enhance w/ gadolinium on T1+high signal on T2)

Question 24

Antiviral treatment for polio

Answer 24

Acyclovir (EBV, VZV, HSV), Ganciclovir/foscarnet (CMV), baclofen +/- BZD +/- tizanidine (chronic spasticity)