CIS Clinical Approach to Peripheral Neuropathies Flashcards
What structure can be compromised in certain disease processes that will lead to the death of a neuron
Vasa Nervorum
blood vessels to the nerves
What does Wallerian degeneration do to the nerve
as the myelin degenerates, the axon following that tract will send off projections to find a tract to be a part of.
What is a radiculopathy
Nerve root dysfunction caused by a structural or nonstructural insult to the root
What are the most common spinal levels involved in Radiculopathy
Cervical C6, C7 root compression
Lumbar L5, S1 root compression
If a pt comes in complaining of scapula, shoulder, and elbow forearm pain, loss of sensation in the 3rd digit and has wrist and elbow extension weakness and no triceps DTR. What nerve root is compromised
C7
What will likely separate an L5 v an S1 Radiculopathy
Absent Achilles Reflex in S1 but no reflex loss in L5
Describe Parsonage-Turner Syndrome
Plexopathy
Severe pain in shoulder followed by weakness and atrophy
spontaneous recovery in 6-18 mo; steroid can help early on
What is a mononeuropathy
Single nerve affected with specific pattern of sensory loss
Carpal Tunnel and Cubital Tunnel
What is a polyneuropathy
Diffuse, symmetrical disease.
Stocking, glove sensory loss with distal weakness
eg Diabetic neuropathy
What is mononeuropathy multiplex
Focal involvement of two or more nerves
May occur in systemic disorders
Describe paresthesia
secondary to large myelinated fiber disease (pins and needles)
Name the sensory deficits in the disease of Large myelinated sensory fibers
impairment of
light touch
two point discrimination
Vibration
proprioception
What senses are lost in damage to small unmyelinated fibers
Temperature
Pain (pinprick)
If you wanted to test if anterior interosseous syndrome was present, what would you do
Make the OK sign. If their thumb and index finger are flat then it is a positive sign.
What are common sites of ulnar mononeuropathies
Axilla
Elbow
Cubital tunnel
Wrist
What is froment sign in ulnar neuropathy
Have someone grab a piece of paper. If thumb is flat then that is normal. Flexed thumb is positive and indicates neuropathy
What are common sites for radial mononeuropathy
Axilla (crutch)
Humerus/Spiral Groove (Tanner’s Palsy, AKA Saturday night Palsy
Supinator
Wrist
What are the signs of radial mononeuropathy
Wrist drop.
In peroneal nerve entrapment, what is the location, predisposing action, and sx
Location: Fibular neck
Actions: Leg Crossing, squatting
SX: Foot drop, weak evertors, sensory loss in dorsum of foot
In femoral cutaneous nerve entrapment, what is the location, predisposing action, and sx
Location: Inguinal Ligament (meralgia paresthetica)
Actions: Tight Clothing, weight gain (AKA gun belt palsy)
Sensory loss in lateral thigh
What test can be used to assess proprioception in peripheral neuropathy
Romberg Maneuver
If you have a paraneoplastic peripheral neuropathy, what is the deficit likely to be
Pure sensory (dorsal ganglionopathy)
Describe small fiber polyneuropathy
Pain or burning and loss of pain and temp sensation
EMG/NCV normal
Decreased epidermal nerve fiber density
What is the most common identifiable cause of neuropathy in the US
Diabetes Mellitus
What is the most common Hereditary Motor Sensory Neuropathy
HMSN I AKA Charcot-Marie-Tooth
demyelination
Describe HMSN 1 AKA Charcot-Marie-Tooth I
AD pattern inheritance 1st-2nd decade onset Difficulty walking/running Develop Pes cavus, hammer toe EMG slowing of motor nerve conduction
What is the main difference between HMSN I and II
EMG shows normal motor nerve conduction velocities in HMSN I
Describe Guillain-Barre syndrome
Acute ascending motor paralysis
Following EBV, Campylobacter
HIV
Hodgkin’s disease
What are the key lab findings in Guillain-Barre syndrome
CSF: Albumino-cytologic dissociation (increase protein, normal cell count)
NCVs: slow conduction velocity, focal conduction block, prolonged F waves
Someone has GBS, and they NCV/EMG shows low amplitude and denervation, what is the prognosis
BAD
In 5% of GBS, pts will develop Miller-Fisher Syndrome. What is that biz
ophthalmoplegia, ataxia, areflexia
facial weakness, dysarthria, dysphagia
GQ1b and GT1a antibodies
How does Chronic Inflammatory Demyelinating Polyneuropathy compare to AIDP
Slower to evolve and persistent
May occur spontaneously or after GBS
Does EMG/NCV lead to specific diagnosis
nope
