Neuromuscular Flashcards

1
Q

Fibrillation

A

Abnormal spontaneous activity

  • spontaneous depolarization of single muscle fiber; ACTIVE DENERVATION
  • REGULAR
  • -> neuropathic disease
  • ->some myopathies (inflammatory, dystrophies)
  • -> Severe NMJ (Botulism)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Positive sharps

A

Spontaneous depolarization of single muscle fiber

-ACTIVE DENERVATION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Spontaneous Activity: Muscle fiber and multiple muscle fibers

A
  • Fibrillation
  • Positive wave
  • Myotonia
  • Complex repetitive discharges (CRD); multiple muscle fibers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Myotonia

A

Spontaneous muscle fiber discharge

  • waxing/waning amplitude and frequency
  • ->myotonic dystrophy
  • ->myotonia congenita
  • ->paramyotonia congenita
  • ->hyperkalemic periodic paralysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Complex repetitive discharges

A

spontaneous depolarization of single muscle fiber, followed by ephaptic spread to adjacent denervated fibers AND reactivation of initial pacemaker fiber (loop)

  • -> chronic neuropathy
  • -> myopathy with denervation (i.e. necrotic, inflammatory)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Spontaneous Activity: Motor neuron/axon

A
  • Fasiculation
  • Myokymia
  • Tetany
  • Cramp
  • Neuromyotonia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Fasciculation

A
  • single, spontaneous, involuntary depolarization/discharge of motor unit
  • IRREGULAR
  • **doublet/triplet/multiplet: MUAPs fire in groups of 2/3/multiple
  • characteristic of tetany from hypoCa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Myokymic

A

rhythmic, grouped, spontaneous dicharges of same motor unit

  • -> radiation injury i.e. brachial plexopathy
  • -> GBS
  • -> MS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Cramp

A

high frequency, irregular repetitive discharges of several normal MUAPs.
-benign or associated wtih neuropathic, metabolic, endocrinologic conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Neuromyotonic

A

high frequency, decrementing repetitive discharges of single motor unit

  • delayed muscle relaxation
  • ->autoimmune VGKC channelopathy
  • ->chronic neuropathy (i.e. SMA, polio)
  • associated with other findings i.e. fascics, myokymia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

MUAP morphology-polyphasia

A

-measure of synchrony of muscle fibers within motor unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

MUAP morphology-satellite potentials

A

-seen in early reinnervation (by collateral sprouts from adjacent units)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

MUAP morphology-Neuropathic

A

Acute axonal loss: normal morphology, decreased recruitment

  • reinnervation doesnt occur for weeks/months
  • loss of motor units (decrease recruitment)
  • also see this pattern in demyelinating with conduction block

Chronic axonal loss, partial denervation: large, polyphasic, inc duration and amplitude (reinnervation of denervated muscle fibers occurs via collateral sprouting by adjacent axons–> MUAPs inc duration, inc amplitude

Chronic Axonal loss with complete denervation:
small, polyphasic, small amp, short duration, polyphasic, DECREASED recruitment
-reinnervation occurs via axonal growth (no surviving axons to sprout)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

MUAP-myopathic

A

Acute: short duration, small amplitude, polyphasic, EARLY recruitment

  • fewer muscle fibres per motor unit
  • polyphasia due to dyssynchronsous firing of muscle fibers

Chronic: small amplitude, LARGE polyphasic units (look up why)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly