Electrotherapy
Introduction:
The concept of electricity as a therapeutic agent is not a recent
innovation. The use of electricity for therapeutic purposes has grown in
the recent years and now includes a wide variety of apparatus. The
literature contains many early references to the use of electricity as a
therapeutic tool, not only for experimental trials but also for clinical
purposes. Nowadays, some of the standard terminology used in the field
of electrotherapy is named for the early workers, such as Michael
Faraday for “faradic current” and Luigi Galvani for “galvanic
current”.
Basic physics, of which electricity is one branch, also includes the
science of light, heat, cold and sound. As physical therapists, we use all
of these natural phenomena in our daily practices, adapting them to our
specific medical needs. So, the term “physical therapy” can also be
adapted to be “applied physics”.
The electromagnetic spectrum, ranging from radio and TV
transmission to gamma radiators, is the source for most of the
electrotherapy modalities. Receiving radiation from the sun, the human
body is able to separate each component according to its anatomical
make-up and need. So, the human body absorbs bands in the spectrum for
physiologic effects, specific to that range of wavelengths or frequencies.
For example, the absorption of infrared radiation (7.700 - 150.000 A°
units band) occurs as heat to the 3-mm level of skin. The absorption of
ultraviolet radiation (150 - 3.900 A° units band) occurs at the 1-mm level
of skin, where chemical changes produce sunburn and enhance some
metabolic processes. In the practice of physical therapy, it is available to
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produce these various bands of energy artificially to apply them in the
form of therapeutic modalities.
When applying electric modalities to patients, it is essential to the
physical therapist to respect the electrical nature of the human body. An
appreciation of the body’s electrophysiology and the electrical qualities
of the selected modality are essential for appropriate treatment. As the
human body functions by electricity, its mal-function can also be
measured by using electricity. Many diagnostic procedures are available
now such as electro-cardiogram (ECG), electro-encephalogram (EEG)
and electro-myogram (EMG).
Recent developments:
Among the newer modalities of electrotherapy is the cold laser.
Although laser light is produced within the segment of the visible
spectrum, it does not act as ordinary light. It has been found that laser
light has unusual favorable effects on human metabolic processes.
Other recent developments in the field of electrotherapy present
themselves in using the existing modalities with variations in waveforms,
amplitudes, polarities and all other parameters. Nothing new has been
discovered in the basic electro-physics, but many new adaptations and
applications have been established due to the findings in studies of human
neurophysiology. As more information concerning the operation of the
human systems is made available, new and effective techniques must be
designed to optimize therapeutic applications.
Another recent addition to the field of human science has been the
concept of endorphins and their role in pain control. The body production
of its own natural painkiller, beta-endorphin, is believed to be greatly
enhanced by the administration of an electric current to the surface of the
body. Pain normally triggers the production of this chemical agent, which
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provides an analgesic effect. Electrical stimulation, though not painful,
will also trigger endorphin production and dissemination within the
human system. So, the standard electrical muscle stimulation, designed to
elicit contractions as an exercise modality, may act as a stimulant for pain
control through increasing the amount of endorphin released.
As mentioned before, the key to successful practice in
electrotherapy is the knowledge of basic physics of each modality. So, the
most important point to be put into consideration is to know why this
specific treatment modality has been selected. Generally speaking, the
road to effective treatment should pass through:
 Skillful selection of modality.
 Administration of effective treatment
 Appropriate adaptation of treatment procedures.
 Accurate evaluation of the results.
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