Question 1

What is a "motor point"?
A) Location of receptors in the skin that best respond to electrical stimulation
B) Place where the greatest motor response is found for a given amount of stimulation
C) Point over a muscle where point stimulation will locate greatest resistance to current
D) Hypothetical location of alpha motor neuron in the muscle

Accepted Answer

Motor points are defined as the points over a muscle where the greatest motor response is found for a given amount of stimulation. These points have the lowest threshold for activation, and thus, require the least amount of electrical stimulation to elicit a motor response. Motor point stimulation is commonly used in electrotherapy for muscle reeducation, strengthening, and pain management.

Question 2

Which of the following most likely explains the physiological response to noxious-level stimulation (hyperstimulation) that results in analgesia?
A) Release of endogenous opioids in the central nervous system
B) Closing the "gate" to nociception in the spinal cord
C) Blocking of nociceptive receptors in the skin
D) Release of histamine and prostaglandins into the circulatory system

Accepted Answer

The release of endogenous opioids in the central nervous system is the most likely explanation for the analgesic response to hyperstimulation. These opioids include substances such as endorphins, which act as natural painkillers and can be released in response to noxious stimuli. Blocking nociceptive receptors in the skin and releasing histamine and prostaglandins would not lead to analgesia, and while closing the "gate" to nociception in the spinal cord can reduce pain transmission, it is not the most likely explanation for the observed response.

Question 3

What will happen to the current density under each electrode if lead wires are bifurcated and attached to multiple electrodes?
A) Decreased at each individual electrode
B) Increased at each individual electrode
C) Decreased at the original electrodes and increased under the newly added electrodes
D) No change

Accepted Answer

When lead wires are bifurcated and attached to multiple electrodes, the total current is distributed among more electrodes, leading to a decrease in current density at each individual electrode.

Question 4

Which electrode choice below is most appropriate when the goal of electrical stimulation is to produce a strong muscle contraction in a large muscle group, such as the quadriceps?
A) Any size electrode will work as long as it is over the motor point of the muscle.
B) Large electrodes will help disperse the current over a larger area to improve patient tolerance.
C) Small electrodes are best because motor threshold stimulation requires a high current density.
D) A probe electrode is best because it focuses the stimulation on the motor points of the muscle.

Accepted Answer

Large electrodes will help disperse the current over a larger area, reducing the risk of discomfort or skin irritation and improving patient tolerance. In addition, a large surface area will allow for a greater number of muscle fibers to be recruited, leading to a stronger muscle contraction.

Question 5

Which of the following statements best summarizes the research on neuromuscular electrical stimulation (NMES) for muscle strengthening?
A) The strength benefits of NMES are superior to no exercise at all for healthy muscle.
B) In the initial periods of rehabilitation the strength benefits of NMES are not superior to voluntary exercise in weakened muscle.
C) There is no correlation between the intensity of NMES and strength gains.
D) NMES is no better than exercise for strengthening healthy muscle.

Accepted Answer

NMES has been shown to provide strength benefits superior to no exercise at all for healthy muscle, making it a useful tool in certain rehabilitation and training contexts.

Question 6

When using balanced biphasic pulsed current for treatment, what is the correct attachment of the lead wires to the electrodes?
A) The red wire must be attached to the anode and the black wire to the cathode.
B) The red wire must be attached to the cathode and the black wire to the anode.
C) The red wire must be attached to the dispersive pad and the black wire to the smaller electrode.
D) Wire color does not matter for this type of current.

Accepted Answer

In balanced biphasic pulsed current, the current alternates direction, making one electrode act as the anode and then the cathode in alternating pulses. Therefore, wire color does not impact the treatment outcome because there is no consistent anode or cathode.

Question 7

What is the relationship between current density and electrode size?
A) Current density is directly proportional to electrode size.
B) Density depends on the intensity of the current and not electrode size.
C) For every square centimeter of electrode there is a twofold increase in density.
D) Current density is inversely proportional to electrode size.

Accepted Answer

Current density is inversely proportional to electrode size. This is because as the electrode size increases, the total surface area for the current to flow through also increases, causing a decrease in current density. The opposite is true for smaller electrodes, where the surface area is limited, causing an increase in current density.

Question 8

Which of the following is the correct equation for determining the dosage for iontophoresis treatments?
A) Dosage (μA·pps) = Current (μamp) × Frequency (pps)
B) Dosage (mA·min) = Current (mA) × Duration (min)
C) Dosage (V·sec) = Voltage (V) × Duration (sec)
D) Dosage (V/pps) = Voltage (V) × Frequency (pps)

Accepted Answer

The correct equation for determining the dosage for iontophoresis treatments is Dosage (mA·min) = Current (mA) × Duration (min). This equation takes into account both the strength of the current and the length of the treatment, which are the two main factors in determining the dosage. The other options either include incorrect units or are not specific to iontophoresis treatments.

Question 9

Which of the following will occur in a constant current (CC) device if the resistance to current flow in biological tissues increases?
A) Voltage will increase.
B) Current will increase.
C) Voltage will decrease.
D) Current will increase

Accepted Answer

In a constant current device, if the resistance increases, the voltage will automatically adjust upwards to maintain the set current level. This is because, according to Ohm's Law (V = IR), voltage (V) must increase if resistance (R) increases while keeping current (I) constant.

Question 10

Patients with vasospastic disorders may benefit from which of the following types of stimulation to improve peripheral blood flow?
A) NMES to large muscles closest to the body part that is affected
B) Iontophoresis with dexamethasone
C) Motor-level stimulation for 15 to 30 minutes
D) Subsensory stimulation using direct current for 10 to 15 minutes

Accepted Answer

Motor-level stimulation can increase blood flow and improve circulation, which may benefit patients with vasospastic disorders.

Question 11

When performing electrical stimulation for tissue healing, galvanotaxis may help promote healing of the wound because
A) Galvanotaxis has a bacteriocidal effect.
B) Histamine and prostaglandins are released into the wound.
C) Calcium fluxes facilitate depolarization of excitable cell membranes.
D) Cells associated with healing migrate toward the opposite-charge pole in the electric field.

Accepted Answer

Galvanotaxis refers to the migration of cells in response to an electric field. In electrical stimulation for tissue healing, cells associated with healing such as fibroblasts and endothelial cells are believed to migrate towards the opposite-charge pole in the electric field, thus promoting healing of the wound.

Question 12

Inhibition of edema following trauma may be effective if the following is performed
A) Sensory level stimulation for 10 minutes every hour for the first week following trauma
B) Motor level stimulation for 30 minutes two to three times a day for the first 2 days after trauma
C) Sensory level stimulation for 30 minutes or several hours during the first 24 to 72 hours
D) Neuromuscular electrical stimulation (NMES) performing rhythmic contractions of muscles in the area of the trauma

Accepted Answer

Sensory level stimulation for 30 minutes or several hours during the first 24 to 72 hours has been shown to be effective in inhibiting edema following trauma. Motor level stimulation and NMES may have other benefits but are not specifically indicated for edema inhibition.

Question 13

Which pair of parameters is most commonly varied or manipulated to elicit the various forms of TENS such as conventional, acupuncture, and burst train?
A) Frequency and amplitude
B) Frequency and rise time
C) Frequency and pulse duration
D) Pulse duration and waveform shape

Accepted Answer

Frequency and Pulse Duration are the most commonly varied or manipulated parameters to elicit the various forms of TENS such as conventional, acupuncture, and burst train. Frequency refers to the number of electrical pulses delivered per second, while pulse duration is the length of time each electrical pulse lasts.

Question 14

Which of the following is NOT believed to occur during treatments using iontophoresis?
A) Electromigration
B) Electroporation
C) Electrosaturation
D) Electroosmosis

Accepted Answer

Electrosaturation is not a known mechanism that occurs during treatments using iontophoresis. Electromigration, electroporation, and electroosmosis are all mechanisms that can occur during iontophoresis.

Question 15

Which of the following electrode placements is best for achieving a contraction of the wrist extensors?
A) One electrode proximal near the elbow and the other distal near the wrist
B) Cross-section arrangement on the forearm, one anterior and one posterior
C) Close together over the wrist extensor muscles in the forearm
D) One large electrode over the muscle belly and a smaller electrode distally near the wrist

Accepted Answer

Placing electrodes close together over the wrist extensor muscles in the forearm targets the specific muscle group effectively for contraction.

Question 16

When performing motor-level stimulation for pain control, what clinical response is expected?
A) Comfortable tingling or buzzing feeling in the area of pain
B) Muscle twitching, which may be accompanied by prickling and stinging sensations
C) Muscle contraction and a feeling of deep pressure in the muscle
D) A painful sensation under the electrodes that may cause anesthesia

Accepted Answer

Muscle twitching, which may be accompanied by prickling and stinging sensations, is the expected clinical response when performing motor-level stimulation for pain control.

Question 17

Which of the following best describes the goal of functional electrical stimulation (FES)?
A) Increased strength of stimulated muscles
B) Facilitation and improvement of purposeful movement
C) Prevention of loss of sensation in neurologically involved limbs
D) Decreased pain to enable functional activities

Accepted Answer

The goal of functional electrical stimulation (FES) is to facilitate and improve purposeful movement. FES uses electrical impulses to stimulate nerves and muscles to create contractions, which can help individuals with neurological impairments regain movement and function. Increased strength may be a secondary outcome of FES, but it is not the primary goal. FES may also not be aimed at preventing loss of sensation or decreasing pain.

Question 18

Which of the following statements is correct regarding electrode placement?
A) Current will travel through deeper tissues when electrodes are closer together.
B) Electrodes can overlap one another up to one-third of the area of the electrode.
C) The best electrode placement for a given treatment may require some trial and error.
D) Electrodes should not be placed directly over peripheral nerve trunks.

Accepted Answer

The best electrode placement for a given treatment may require some trial and error. This is because each patient's anatomy and pain location may vary, and the therapist may need to adjust the placement of electrodes to provide maximal pain relief. Option A is incorrect because current will travel through deeper tissues when electrodes are farther apart, not closer together. Option B is incorrect; electrodes should not overlap one another. Option D is also incorrect because electrodes can be placed directly over peripheral nerve trunks, but caution should be taken to minimize the risk of nerve stimulation or damage.

Question 19

Which of the following correctly describes "pulse duration"?
A) Time from the beginning of the first phase to the end of the second phase
B) Total time elapsed from beginning to end of all phases, including interphase interval
C) Total time elapsed from beginning to end of all phases, not including any interphase intervals
D) Time of one pulse, not including any phases or intervals

Accepted Answer

The answer of Which of the following correctly describes "pulse...

Question 20

How often can a typical disposable electrode be reused before it should be discarded?
A) Once
B) Twice
C) Depends on the amount of adhesive gel that is applied to the electrode
D) 15 to 20 times

Accepted Answer

Disposable electrodes are designed to be used only once. Reusing them can lead to inaccurate readings and skin irritation.

Quiz 10: Clinical Electrical Stimulation: Application and Techniques

What is a "motor point"?

Which of the following most likely explains the physiological response to noxious-level stimulation (hyperstimulation) that results in analgesia?

What will happen to the current density under each electrode if lead wires are bifurcated and attached to multiple electrodes?

Which electrode choice below is most appropriate when the goal of electrical stimulation is to produce a strong muscle contraction in a large muscle group, such as the quadriceps?

Which of the following statements best summarizes the research on neuromuscular electrical stimulation (NMES) for muscle strengthening?

When using balanced biphasic pulsed current for treatment, what is the correct attachment of the lead wires to the electrodes?

What is the relationship between current density and electrode size?

Which of the following is the correct equation for determining the dosage for iontophoresis treatments?

Which of the following will occur in a constant current (CC) device if the resistance to current flow in biological tissues increases?

Patients with vasospastic disorders may benefit from which of the following types of stimulation to improve peripheral blood flow?

When performing electrical stimulation for tissue healing, galvanotaxis may help promote healing of the wound because

Inhibition of edema following trauma may be effective if the following is performed

Which pair of parameters is most commonly varied or manipulated to elicit the various forms of TENS such as conventional, acupuncture, and burst train?

Which of the following is NOT believed to occur during treatments using iontophoresis?

Which of the following electrode placements is best for achieving a contraction of the wrist extensors?

When performing motor-level stimulation for pain control, what clinical response is expected?

Which of the following best describes the goal of functional electrical stimulation (FES) ?

Which of the following statements is correct regarding electrode placement?

Which of the following correctly describes "pulse duration"?

How often can a typical disposable electrode be reused before it should be discarded?