22: Peripheral Neuropathy Workup - Frush

Question 1

nature of peripheral neuropathy

Answer 1

burning, tingling, electrical sensations, numbness

“feet on fire” creepy, crawly sensation

Question 2

location of peripheral neuropathy

Answer 2

early - toes and met heads

works way up foot and leg

Question 3

only a couple of toes numb

Answer 3

not peripheral neuropathy more likely neuroma

also not going to be unilateral

Question 4

pain worse at ____

Answer 4

night

pain will turn to numbness

Question 5

associated derm changes

Answer 5

xerosis
fissures
calluses
ulcers

muscle wasting can cause hammering of digit and prominent met heads

loss of balance and temp changes

massaging area will temporarily help

Question 6

___ of pts with DM and PN will have other cause for PN

Answer 6

10%

Question 7

causes of PN: I’M DISTAL

Answer 7

I - idiopathic, inherited ( charcot marie toothe)
M - metabolic, mechanical (DM, radiculopathy, nerve entrapments)
D - drugs (chemotherapy)
I- infection (leprosy, myasthenia gravis, syphillis)
S - sarcoidosis
T - toxins, thyroid (uremmia, havy metals, alcohol)
A- autoimmune, allergy (GBS, lupus)
L - lack of vitamins 9B12 insufficiency, ulcerative colitis, crohn’s)

Question 8

what gait might you see with PN?

Answer 8

ataxic gait

Question 9

type A fibers v. type B fibers v. type C fibers

Answer 9

A: heavily meylinated, bigger, faster, acute pain, temperature, touch, pressure, proprioception, somatic efferent fibers

B: moderate-velocity, less heavily myelinated, visceral afferent, preganglionic autonomics

C: slower, umyelinated, slowe-velocity, chronic pain psotganglionic autonomic

Question 10

loss of ___ of 10 areas to diagnose PN with SWM

Answer 10

4

if 0/10 felt keep testing up leg to knee to find level of sensation

needs to be 5.07 monofilament that exerts 10 g of pressure

Question 11

look at picture of 10 places to touch

Answer 11

9 on plantar surface, 1 dorsal

Question 12

test vibratory perception with tuning fork =

Answer 12

128 hx tuning fork applied to 1sta nd 5th mpj

practitioner should be able to feel for 5 sec longer than pt (if more than 10 sec = nerve damage)

Question 13

biothesiometer =

Answer 13

machine that vibrates at 100Hz

vibratory perception - more accurate than tuning fork

a mean of 3 reading over 25V indicates PN

Question 14

device that tests 1 and 2 pt discrimination

Answer 14

pressure-specificty sensory device

Question 15

MRI is useful if you think the problem is stemming from…

Answer 15

spinal stenosis
lumbar disk disease
spinal cord tumor

Question 16

which nerve is usually biopsied?

Answer 16

sural n.

Question 17

what blood testing info would you want?

Answer 17

blood glucose, HgA1C
B-12 folate
heavy metals
creatinine liver profiles
ANA

Question 18

most common cause of PN

Answer 18

diabetic neuropathy