Week 6 Review

Question 1

Electrical stimulation to produce contractions of innervated muscles is known as:

Answer 1

NMES

Question 2

What is the purpose of a ramp-up time?

Answer 2

for patient comfort

Question 3

The minimum MVIC (Max Volitional Isometric Contraction) force required for strengthening healthy muscle using NMES is:

Answer 3

50% of MVIC

Question 4

When the goal for NMES is to increase strength, what ratio of on:off time should be used initially?

Answer 4

1:5

Question 5

If the muscle twitches, instead of producing a strong contraction, what parameter should you change?

Answer 5

frequency

Question 6

This type of current is required for denervated muscle to contract

Answer 6

direct current

Question 7

With electrically stimulated contractions, the contraction force can be increased by increasing the total amount of current, which can be achieved by (select all that apply):

Answer 7

-increasing the pulse duration
-increasing the current amplitude
-increasing the electrode size (using larger electrodes)

Question 8

NMES to the quadriceps can improve muscle strength but does little to improve functional outcomes in patients with reduced physical activity, muscle atrophy, and loss of strength associated with progressive or critical illness.

Answer 8

False (NMES to the quadriceps can improve muscle strength AND functional outcomes in patients with reduced physical activity, muscle atrophy, and loss of strength associated with progressive or critical illness.)

Question 9

In general, whether the contraction is stimulated by electrical stimulation or done voluntarily, strength gains in healthy muscle depends on the force of the contraction. For strength gains to occur, the contraction must be at least ___ of the maximum voluntary isometric contraction (MVIC) force.

Answer 9

50%

Question 10

In general, in terms of the pulse duration setting for stimulating muscle contraction, ___ durations are usually more comfortable for stimulating smaller muscles, and ___ durations are more comfortable for stimulating larger muscles.

Answer 10

shorter; longer

Question 11

For NMES, selection of the ideal combination of pulse duration and current amplitude should be based on patient comfort and achievement of the desired outcome.

Answer 11

true

Question 12

When applying NMES to stimulate a muscle, you notice that the contraction is very twitchy (as opposed to a smooth tetanic contraction). The electrode placement and size are correct, as well as the pulsed biphasic waveform. In this case, what setting is the most likely cause for a twitchy contraction?

Answer 12

the frequency is too low

Question 13

For NMES, a frequency of at least ___ is needed to produce a sustained contraction. A frequency of ___ is generally recommended to produce a smooth tetanic contraction without causing rapid fatigue.

Answer 13

30 pps; 35-50 pps

Question 14

When the goal of e-stim is to relieve a muscle spasm, the on:off ratio is set at ___, with both on and off times set between ___. These settings will produce muscle fatigue and relax the spasm.

Answer 14

1:1; 2-5 seconds

Question 15

When e-stim is used for muscle strengthening, it is generally recommended that treatment last long enough to allow for ___ contractions. This will usually take about ___.

Answer 15

10-20; 10 minutes

Question 16

When applying NMES for a muscle contraction, a commonly overlooked setting that is often the culprit of a poor contraction is:

Answer 16

electrode placement

Question 17

Application of an electrical current to produce muscle contractions that are applied during a functional activity. Examples of this include the electrical stimulation of dorsiflexion during the swing phase of gait and the stimulation of write extension and finger flexion during grasp activities.

Which of the following terms does the above definition describe:

Answer 17

FES

Question 18

Increases in strength of the quadriceps following the first 2 weeks of neuromuscular electrical stimulation (NMES) treatments are most likely secondary to which of the following?

Answer 18

Changes in motor unit recruitment

Question 19

Which of the following is the key factor in the efficacy of NMES strengthening protocols?

Answer 19

intensity of training

Question 20

Which of the following parameters can be increased to help limit fatigue during NMES?

Answer 20

off - time

Question 21

Electrode placements for NMES applications depend on which of the following?

Answer 21

Size and location of the targeted muscle

Question 22

An advantage of NMES recruitment of muscle fiber type compared to voluntary recruitment is which of the following?

Answer 22

Activation of fast fibers at lower contraction intensities

Question 23

Which parameters would most likely be effective when the goal of NMES is to enhance strength?

Answer 23

75 pps, 10 seconds on : 50 seconds off, 10 minutes

Question 24

Select an appropriate electrode placement for ambulation assist in a person with decreased active dorsiflexion during the swing phase of gait.

Answer 24

Peroneal nerve and anterior tibialis muscle belly

Question 25

NMES applied to the antagonist muscle for patients with spasticity will reduce spasticity based on which of the following theories?

Answer 25

Reciprocal inhibition of the spastic agonist muscle

Question 26

Studies have shown that NMES for patients with neurological problems who have muscle weakness

Answer 26

May help increase muscle strength, especially in the stroke population