PTE 732: quiz questions

electrical modalities

The pulse duration includes all of the following EXCEPT:

interpulse interval

All of the following are synonymous pairs EXCEPT

current, voltage

Which of the following statements is true?

It is possible to stimulate sensory, motor, and pain fibers simultaneously

All of the following cause high impedance to current flow EXCEPT

water

Changing the ramp-up time will

affect when the series of pulses reaches peak amplitude

Is it possible to stimulate only sensory fibers with a device that has a fixed pulse duration of 200 microseconds?

yes, by using a low amplitude

How could the pulse duration of a current be decreased without changing the frequency?

the interpulse interval must increase

Which of the following pulse durations would be the best choice for producing a muscle contraction?

200 microseconds

For an interferential current, what happens to the beat frequency when the frequency of one of the circuits is decreased from 4100 Hz to 4050 Hz and the frequency of the other circuit stays fixed at 4000 Hz?

decreases

When two alternating currents cross paths and the peak of one current intersects with the trough of the other current, what is the result?

the currents will summate to produce zero current amplitude at the area of interference

All of the following are proposed advantages of using interferential current EXCEPT:

ability to produce muscle contractions

Regarding action potentials (AP), which one of the following statements is true?

increasing current amplitude will increase the number of nerve fibers stimulated

Which of the following changes to an electrical stimulation current will most effectively increase the number of APs generated?

increasing the frequnecy

To reduce the likelihood of adaptation, devices have been engineered to modulate (i.e., automatically vary during a treatment) all of the following characteristics EXCEPT:

type of waveform

it would be LEAST appropriate to use a current that had an on:off time option for

pain control with “conventional TENS”

which type of current is used for iontophoresis?

DC (direct current)

which one of the following statements regarding iontophoresis is true?

drugs used for iontophoresis must be water-soluble

Your patient complains of pain and has swelling at the right lateral ankle after an inversion sprain yesterday. You have chosen the following electrical stimulation parameters for treatment: monophasic PC with a fixed pulse duration of 40 microseconds, frequency of 120 pps, amplitude at 90% of motor threshold, electrode of negative polarity at the lateral ankle. The best rationale for this treatment is:

decrease pain and retard edema formation (straight from questions don’t come for me!)

If a patient reported being unable to feel a current with 100 pps frequency during a TENS treatment, which of the following changes is most likely to produce a sensation?

increasing the current amplitude

a beat is produced by interference of which of the following types of current?

alternating

After having stimulated a muscle contraction with a 35 pps frequency current, which of the following pulse frequencies is most likely to increase the force of a second contraction?

80 pps

one can increase the depth to which a current penetrates by:

increasing the distance between electrodes

biphasic PC may be effective for all of the following EXCEPT:

to prevent muscle atrophy in denervated muscles

All of the following are examples of using functional electrical stimulation (FES) in treatment EXCEPT:

to control pain in the hemiplegic shoulder

Theoretical rationale(s) for using neuromuscular electrical stimulation (NMES) for muscle strengthening include

both a and b

• greater strength gains will occur when training with higher foce muscle contractions

• electrical stimulation recruits more large motor neurons and thus more type II muscle fibers

For a patient receiving neuromuscular stimulation (NMES) to increase biceps and brachialis strength, which of the following electrode configurations is most likely to maximize elbow flexion force using 2-inch electrodes?

two electrodes placed parallel to the muscle fibers, 2 ½ inches apart

Which of the following parameter(s) is/are different for conventional TENS and acupuncture-like TENS?

all of the above

• frequency

• pulse duration

• amplitude

All of the following are contraindications for the use of electrical stimulation (ES) EXCEPT:

ES near an open wound

Which scenario is LEAST likely to cause burns?

one electrode falls off