Approach to Peripheral Neuropathies Flashcards
What feeds nerves with nutrients and blood?
Vasa Nervorum
If a peripheral nerve is myelinated it has a ____ conduction speed
FAST
If a peripheral nerve is unmyelinated, it has a ____ conduction speed
Slow
What is a Radiculopathy?
Nerve root dysfunction
Skin area supplied by a single spinal root
Dermatome
Muscle group supplied by a single spinal root
Myotome
Area of bone supplied by a single spinal root
Sclerotome
In the Cervical region, what level/nerve root is most commonly compressed?
Level = C6-C7
Nerve root compressed = C7
Most common etiology of Brachial Plexopathy?
Compression/stretch with CABG for ex.
Parsonage-Turner Syndrome is a Brachial Plexopathy. Where is there pain, weakness and atrophy?
Shoulder area
Single nerve affected with specific sensory loss and weakness
Mononeuropathy
Stocking/glove sensory loss with distal weakness
Polyneuropathy
Focal involvement of 2+ nerves with some systemic disorders like DM/vasculitits
Mononeuritis Multiplex
Which motor neurons are affected with Peripheral neuropathies?
LMN
DTRs with Peripheral Neuropathies
Hypoactive
Distal paresis, atrophic muscles and flaccid tone characterize central or peripheral neuroapthies?
Peripheral neuropathies
Carpal Tunnel Syndrome traps which nerve and where will pain/numbness/paresthesias be felt?
Median Nerve
= Thumb and first 2 fingers
What is another syndrome besides Carpal Tunnel Syndrome that can trap the Median Nerve?
Pronator Syndrome
Where is the pain and when with Pronator Syndrome?
Pain of the proximal forearm and with pronation
What movement can the patient not do if they have Anterior Interosseous Syndrome and what nerve is affected?
They cannot make a good circle when trying to make the “OK” sign
– Median Nerve
What syndrome affects the Ulnar nerve and where?
Cubital Tunnel Syndrome
– At the elbow
What will the patient have an abnormality in if they have an Ulnar Mononeuropathy?
Cannot grasp something well between thumb and first finger
– will have thumb flexion
What is a common Radial Mononeuropathy?
Saturday Night Palsy
As the Radial Nerve is damaged with Saturday Night Palsy, what will the sign be?
Wrist drop
Where is the radial nerve compressed with Saturday Night Palsy?
Spiral groove
What is the most common lower limb entrapment Neuropathy?
Peroneal Mononeuropathy
Where does Peroneal Mononeuropathy usually occur?
Fibular head entrapment
What will be present with Peroneal Mononeuropathy?
Foot drop - loss of dorsiflexion and possible sensory loss on top of foot
If large fibers are affected, what senses will be altered?
Position and vibratory
If small fibers are affected, what senses will be altered?
Pain and temperature
What are the 2 most common causes of Polyneuropathy?
Diabetes
Alcohol
What is the most common Hereditary Polyneuroathy?
Charcot-Marie-Tooth
Hereditary Motor Sensory Neuropathies (HMSN) like charcot-marie-tooth have many forms. Which forms are demyelinating or axonal?
HMSN1 = demyelinating HMSN2 = axonal
What is a unique finding with HMSN1?
Skeletal deformities
– pes cavus and hammer toes
With HMSN1, what will the EMG show and why?
Slowing of motor nerve conduction
– demyelinating type
HMSN2 has similar symptoms to type 1 without the?
No skeletal abnormalities
What will the EMG show with HMSN2 and why?
NORMAL conduction velocities of motor nerve
– Axonal type
Charcot-Marie-Tooth inherited polyneuropathy is also called?
Hereditary Motor Sensory Neuropathies (HMSN)
What usually causes Guillain Barre Syndrome?
Campylobacter Jejuni enteritis
What will be seen in the CSF with Guillain Barre Syndrome?
Increased protein (albumino-cytologic dissociation) with normal cell count
Will the conduction velocity be slowed with Guillain Barre?
Yes
What is the treatment options for Guillain Barre?
Plasmapheresis
IVIg
A poor prognosis with Guillain Barre is associated with?
Low amplitude motor nerves
What is a common variant of Guillan Barre?
Miller-Fisher Syndrome
What antibodies are (+) with Miller-Fisher Syndrome?
(+) GQ1b
(+) GT1a
What are the symptoms of Miller-Fisher Syndrome and what is it a variant of?
Variant of Guillain Barre
= Ophthalmoplegia, ataxia, arreflexia, facial weakness
What antibodies are (+) with Miller-Fisher Syndrome?
(+) GQ1b
(+) GT1a
What is similar to Guillain Barre syndrome but is more persistent?
Chronic Inflammatory Demyelinating Polyneuropathy
How can you treat Chronic Inflammatory Demyelinating Polyneuropathy that you cannot do with Guillan Barre?
Steroids
Immune suppressants
– can still do plasma exchange, IVIg
