BB Lecture 12: Neuromuscular disease localizatoin and DDx Flashcards
Amplitude of motor nerve conduction study
Shows how many axons are in the nerve bundle. Smaller the amplitude, less axons there are.
Nerve Conduction Velocity (motor nerve conduction study)
Can allow you to tell if it is myelination problem. If the nerve conduction velocity is slow, then it is a myelination problem (GBS or MS)
PMP22
charcot marie tooth
HNPP
s
Anterior Horn Cells do NOT affect
eye muscles
Nerve root
shorthand for spinal nerve
Peripheral nerve
neuropathies…axonal
Charcot-Marie-Tooth (CMT1A)
a
HNPP and CMT1A
The most common myelin neuropathies
Nerve Conduction Studies
assess sensory and motor nerve conduction
Repetitive nerve stimulation studies
assess NMJ transmission
Needle EMG
assesses the motor unit (altered in myopathy or diseases affecting the entire nerve or just the motor nerves)
Shows if you have myopathy or motor neuron disease
Motor Unit
a motor nueron and the skeletal muscle fibers innervated by that axon
Compound Muscle Action Potential (CMAP)
The AMPLITUDE that you see during stimulation
If repeated stimulus makes patient feel better, then the lesion is at the
Pre-synaptic terminal
If repeated stimulation cannot resovle the problem, the lesion is at the
post-synaptic terminal
Muscle Tone
Resistance to passive movement (while awake)
Hypotonia does NOT mean weakness!!
Weakness and loss of reflex
indicative of peripheral nerve lesion
Normal CK level
means that dystrophy is very unlikely
Floppy Baby leads to
a myopathy localization
Normal CK level
means that dystrophy is very unlikely
Floppy Baby leads to
a myopathy localization
Lateral horn
a
clarke’s nucleus
a
