Finals: Electrodiagnosis and Electromyography

Question 1

Study of electrical activity in motor units when stimulated by electrical pulse, providing diagnosis and prognosis in the neuromuscular complex.

Answer 1

Electrodiagnosis

Question 2

Assessment Tools in Electrodiagnosis

Answer 2

Includes EMG (Electromyography), ECG (Electrocardiography), and EEG (Electroencephalography).

Question 2

Includes anterior horn cell body and axon, neuromuscular junction, muscle cells, sensory neurons, and Schwann cells.

Answer 2

Motor Unit Components

Question 2

Physiological Basis of Electrodiagnosis - Nerve Fiber Stimulation

Answer 2

Requires stimulation higher than the threshold of excitation (-70 mV).

Question 2

History of Electrodiagnosis - Erb’s Observations

Answer 2

Negative response to faradic shocks.
Positive response to galvanic currents with long duration in muscles deprived of their supply

Question 3

Accommodation in Denervated Muscles

Answer 3

Denervated muscles lack the power of accommodation to slowly increasing stimulation intensities, respond only to interrupted DC with brisk contraction.

Question 4

Physiological Basis of Electrodiagnosis - Muscle Fiber Stimulation

Answer 4

Requires stimulation higher than the threshold of excitation (-90 mV) to induce muscle contraction.

Question 5

A short-lasting event where the electrical membrane potential of a cell rapidly rises and falls, crucial for cell-to-cell communication.

Answer 5

Action Potential

Question 6

Levels of RD and their implication

Answer 6

Partial Reaction of Degeneration (PRD) - Decreased response to tetanizing current.
Complete Reaction of Degeneration (CRD) - No contraction, brisk muscle twitch only.
Absolute Reaction of Degeneration (ARD) - No contraction with any stimulus.

Question 7

Indicates the status of muscle innervation:

Answer 7

Reaction of Degeneration (RD)

Question 7

Indicates long-standing denervation with atrophy and fibrosis, showing no response to both interrupted current and rapid sinusoidal current.

Answer 7

Absolute Reaction of Degeneration (ARD)

Question 8

Indicates neurotmesis with no response to tetanizing current but positive response to interrupted direct current (IDC), resulting in brisk contraction or muscle twitch.

Answer 8

Complete Reaction of Degeneration (CRD)

Question 9

Indicates partial lesion of the motor unit (neuropraxia) with decreased response to tetanizing current.

Answer 9

Partial Reaction of Degeneration (PRD)

Question 10

Involves observing muscle contractions and assessing nerve continuity or lack thereof through evoked potentials.

Answer 10

Nerve and Muscle Potentials Assessment

Question 11

Currents for Testing Reaction of Degeneration

Answer 11

Interrupted current or rapid sinusoidal current using a bipolar technique.

Question 11

In direct current (DC), striated muscle does not contract; muscle contraction occurs only during the opening and closing of the circuit.

Answer 11

Law of Du Bois - Raymond

Question 12

Uses the least current to produce a positive muscle contraction, making it the best method for muscle stimulation.

Answer 12

Cathode Closed Contraction (CCC)

Question 13

For muscles with degeneration and atrophy, the anode is positioned as the active electrode.

Answer 13

Anode Positioning

Question 14

Includes conditions such as poliomyelitis, progressive muscle atrophy, amyotrophic lateral sclerosis, syringomyelia, myasthenia gravis, Lambert-Eaton syndrome, nerve root injuries, neuritis, Guillain-Barre syndrome, muscular dystrophies, infections, and endocrine dysfunction.

Answer 14

Lower Motor Neuron Lesions (LMNL)

Question 15

Involves observation, analysis, and interpretation of bioelectric muscle and nerve potentials using surface or needle electrodes.

Answer 15

Electrophysiological Evaluation

Question 16

Reaction of degeneration test, faradic-galvanic excitability test, strength-duration curve, rheobase, chronaxie, and galvanic twitch-tetanus ratio test.

Answer 16

Traditional Tests

Question 17

Plots the threshold values of stimulation (y-axis) against the duration of the stimulus (x-axis) to assess nerve integrity.

Answer 17

Strength-Duration Curve

Question 18

___is the minimum current intensity required to produce a muscle response.
___is the duration of time that an electrical current twice the rheobase must be applied to elicit a muscle contraction.

Answer 18

Rheobase and Chronaxiez

Question 19

Measures the electrical activity of muscles at rest and during contraction to diagnose motor neuron diseases and other neuromuscular disorders.

Answer 19

EMG

Question 20

Abnormal EMG Activity

Answer 20

Includes fibrillations and abnormal patterns of muscle contraction.

Question 21

Uses auditory, visual, or haptic stimuli to help individuals improve control over neuromuscular processes by providing real-time feedback on muscle activity.

Answer 21

EMG Biofeedback

Question 22

Integrates EMG feedback with relaxation techniques to reduce muscle tension and improve relaxation.

Answer 22

Muscle Relaxation via EMG Biofeedback

Question 23

Electrodes should be placed over the muscle belly, with the anode on the tendon or proximal to the point of stimulation and the cathode over the muscle belly.

Answer 23

EMG Electrode Placement

Question 24

Potential adverse effects include complications related to strengthening and cardiovascular exercises facilitated by EMG.

Answer 24

note

Question 25

Measures the electrical response of the nervous system to a stimulus to test the integrity of peripheral nerves and neuromuscular junctions.

Answer 25

Evoked Potential

Question 26

Assesses the speed and strength of signals traveling through the nerves to determine the state of nerve function

Answer 26

Nerve Conduction Velocities