Exam II Flashcards
(23 cards)
When is NMES for muscle strengthening used?
Healthy individuals
Post-ACL reconstruction
Post-TKA
What is the examination, evaluation, and prognosis for using NMES?
Check history for contraindications and precautions
assess for innervation
assess STR, ROM, sensation, pain, and functional status
What is the recruitment for voluntary contractions?
small motorneurons
small/slow motorunits recruited first
What is the recruitment for NMES contraction?
larger motorneurons
large/fast motorunits may be recruited first (also consider distance)
What is the firing rate for voluntary contractions?
asynchronous firing with varying frequencies
What is the firing rate for NMES contractions?
synchronous firing with frequency of e-stim
What is the type of contraction with voluntary contractions?
maintained and slowly fatiguing
What is the type of contraction with NMES contractions?
greater tendency to fatigue
How do you select a stimulator for NMES?
a portable stimulator may not be as effective d/t power source being a battery.
What are the stimulation parameters for NMES?
current/waveform amplitude/intensity duration/pulse or phase frequency (pulse rate) on/off times ramp times
What are the types of waveforms used with NMES?
pulsed/biphasic symmetrical
pulsed biphasic asymmetrical unbalanced (used when you want one electrode to be more active)
How do you set amplitude when using NMES?
increased intensity increases motorunits recruited
need > or = to 50-60% MVC for strengthening
How do you set duration when using NMES?
200-300 microseconds
decrease duration increase the intensity
increase duration decrease the intensity
How do you set frequency when using NMES?
> 20-30 pps for tetanic contraction
<50 pps to prevent fatigue
How do you set on/off times?
1:1-2 with partial range
1:3-5 with fair to fair+ contraction
increase off time with stronger contractions
How do you set ramp times when using NMES?
mainly for comfort and spasticity
large muscle groups need increased ramp times
What is the original strengthening protocol (developed by Kots for Olympic athletes?
10 contractions per day 10 secs on 50 secs off (but 120 secs off necessary to prevent fatigue) 5 days a week 2-4 weeks >60% MVIC
How do you place electrodes when using NMES?
larger electrodes are more comfortable
place to optimize recruitment of motorunits
common use- monopolar or bipolar (monopolar target electrode is smaller)
How do you monitor NMES treatment?
DOMS
skin reactions
patient’s response
What are the stimulation parameters for EMS of denervated ?
interrupted DC supramax amplitude >1 microsec abrupt or gradual rate of rise frequency varies (tetanizing contraction) treatment times vary
What kind of contraction could occur when directly stimulating muscle?
vermiform contraction (worm like) muscle will stay muscle for 12-18 months without nerve innervation
What are the waveforms used with EMS of denervated muscle?
square (will hit sensory, motor and pain of other nerves)
exponential (use for accommodation of intact nerves in the area-more comfortable)
What is the clinical application of EMS of denervated muscle?
delay of atrophy
nerve regeneration
(could benefit SPC patients)
