Compression Neuropathies Flashcards
What is Carpal Tunnel and what do conduction studies show?
Neuropraxia of median nerve causing numbness in the lateral 3 1/2 fingers, thenar wasting.
It is worse at night
Normal CMAP but low CV
What is a Ulna palsy and what do conduction studies show?
Neuropraxia of ulna nerve causing numbness in medial 1 1/2 finers and hypothenar eminence wasting.
Slow CV after elbow
What is a radial palsy and what do conduction studies show?
Neuropraxia of the radial nerve at the shoulder causing wrist drop and slow CV distal to shoulder
What is Guillian Barre?
An acute, demyelinating, poly ridiculoneuropathy.
Occurs after a viral illness and is widespread low CV.
Manage with heparin and IV immunoglobulins
PERIPHERAL NERVOUS SYSTEM
What is a chronic diabetic neuropathy and what would conduction studies show?
Axonal damage causing low CMAP.
It is chronic and usually starts with loss of sensation.
Can also be caused by drugs and alcohol
What is neuropraxia?
Crushing
What is axonotemisis?
Myelin is cut but schwann cells remain - Wallerian Degeneration
What is neurotemisis?
Complete cutting of nerve
What is myasthenia gravis?
AI against nicotinic receptors causing them to be enveloped and destroyed. it causes fatiguable weakness, particularly around the bulbar muscles
Increased anti ACH and MUSK
Common to get a droopy face
What would you see in a lumbar puncture for GBS?
Raised protein but not WBC
What is the difference between oligodendrocytes and schwann cells?
Schwann - PNS
Oligo - CNS
