EMS COMBINATION 850 Manual page 9

Possible Explanations
It would appear that by applying ultrasound to peripheral nerves, their threshold
to stimulation is reduced, thus making them more sensitive or excitable. It is
likely that this effect is brought about by the alteration of the ion pump activity,
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predominantly Na and K , but also Ca . By altering the transport of these
ions across the cell membrane, the resting potential will be altered and in this
case, it would seem that it results in a reduced threshold for depolarisation.
It is reasonable to expect this situation to exist in other tissues (apart from
nerve) although no direct evidence has been noted to date.
When interferential therapy is applied simultaneously with ultrasound through
the same tissues, a reduced intensity is required in order to achieve the same
physiological / therapeutic effects when compared with interferential therapy in
isolation. This can easily be demonstrated by turning off the ultrasound
component whilst continuing with the interferential therapy. The patient very
soon becomes aware of a much reduced sensation / effect, which can be restored
by restarting the ultrasound.
In addition, the simultaneous application of ultrasound with interferential
therapy minimises the accommodation phenomenon normally associated with
electrical stimulation of the peripheral nerves.
The combination of ultrasound with interferential therapy appears to give rise to
less adverse treatment effects than are associated with the combination of
ultrasound with diadynamic currents, or other electrical stimulations. It has also
been suggested that a greater effective treatment depth can be achieved with
ultrasound - interferential therapy combination.
Unlike routine interferential therapy, the intensity of the electrical stimulation
in combination therapy may need to be REDUCED during treatment, probably
due to the continued effect of the ultrasound on the nerve membrane threshold.
In summary, by combining the two treatment modalities, none of the individual
effects of the treatments are lost, but the benefit is that lower treatment
intensities can be used to achieve the same results, and there are additional
benefits in terms of diagnosis and treatment times.
COMBINATION 850 9 ISSUE 2