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Simultaneous Use of Opioid and Electromagnetic Treatments

Concurrent therapeutic electromagnetic applications complement opioid treatment and promote enhanced pain control.
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Electric Currents

Since the 1970s, electrical nerve stimulation (ENS), has been widely used.7 The best known technique is transcutaneous electrical nerve stimulation (TENS). ENS may be externally administered or is implanted to more directly access nerves. Pain relieving effects can be realized within seconds or minutes. There are two unproven theories as to why ENS may relieve pain. One is a blockage of electrical impulses at the spinal cord level based on the gate control theory of Melzack and Wall.8 The second is a release of endogenous endorphins.9 Acupuncture—particularly if needles are used to administer electric current—is theorized to be effective based on these two theoretical mechanisms. Proposed here is a third possible mechanism: that ENS promotes the mobilization of sequestered electric charges.

A relatively new technique is the use of microelectric currents which have very low amperage. The area of impact may vary from one to two square inches. The electrode pad placed on the skin over the pain site is very small—less than ½ inch in diameter. It administers the current directly into the pain site. Some instruments are using microelectric currents to stimulate alpha brain waves within the skull. This technique is known as cranial electric stimulation (CES). While these cranial, electric techniques may assist psychiatric conditions or otherwise modulate the body’s electricity, there are no accepted theories as to why a peripheral pain site would benefit. Physicians should know, however, that the term “neuromodulation” is now in widespread use and is somewhat based on the belief that an alteration of electrical activity a distance away from the pain site may somehow alter the body’s electric circuitry to relieve pain. It is recommended that this belief be acknowledged but that it requires some evidence that pain can be relieved for considerable time periods using electromagnetic techniques that don’t directly deal with the pain site.

Electric current has been used to deliver medication to pain site by a process called iontophoresis. This technique has had only modest acceptance as the commercial instruments that have been available to deliver medication are very small and cover a skin area that is usually less that 1 to 2 square inches. Also, phonophoresis, the technique that utilizes ultrasound waves, is equal or superior in delivering medication to the pain site.10-12

Diathermy, Infrared, and Ultraviolet Techniques

Diathermy, infrared, and ultraviolet were all initially developed to bring heat to deep tissue.13 All three are waves of the electromagnetic spectrum (see Figure 3). Dia-thermy became the name for shortwave or microwaves. Beginning in the 1950s, there was an attempt to therapeutically use electromagnetic energy rather than a direct electric current. The advantage that this technique brought to medical practice was the ability to direct heat to deep tissues. It found considerable use in sports injuries and some chronic conditions such as hip arthritis.13-15 Research showed that diathermy also caused tissue proliferation and wound healing.14 Diathermy, commercially called “diapulse,” has been removed from the commercial market and is no longer available. A new technique, using the same shortwave frequency (27.12 megahertz) and referred to as radiofrequency, has been brought into the commercial market.16 This upgraded and enhanced electromagnetic treatment is discussed below.

Table 3. Administered Electromagnetic Measures
  • Diathermy
  • Ultraviolet
  • Infrared
  • Ultrasound
  • Pulsed Radiofrequency
  • Electric Current
  • Laser

Ultraviolet and infrared devices were developed to direct heat to deep tissues. They have a shorter electromagnetic wave length than diathermy and are considered light waves. These devices can be hand held and are inexpensive. This author has been unable to identify any reports that infrared or ultraviolet devices have any therapeutic attributes other than deep heat. Nevertheless, heat can be quite therapeutic for some acute and chronic pain sites, and the patient can easily use these devices at home as they are inexpensive, safe, and simple to operate.

Pulsed Radio Frequency

A new effort to utilize electromagnetic energy for pain therapy is a high frequency, pulsed radio wave referred to as “radiofrequency.”3,16 This wave is about the length of one that would play a transistor radio (see Figure 3). It is at the same frequency formerly used in diathermy (27.12 MHz). The wave and frequency used for external pain treatment is not to be confused with the high frequency, heat-producing radiofrequency wave used to ablate tissue during paraspinal interventions.

Pulsed radiofrequency has been extensively used to treat wounds and open sores including the pain and edema surrounding them.16 Use of this technique has demonstrated that high frequency electromagnetic waves cause many tissue elements including collagen, capillaries, and osteoblasts to grow and provide healing.16,17 To date, this modality has been shown to accelerate wound healing, bone growth, and decrease pain and edema around wounds.14-18 This technique is now in early trials for chronic painful conditions such as plantar fasciitis and spine degeneration. As in the case of phonophoresis, early trials indicate that radiofrequency is capable of delivering medication including opioids and corticoids to the pain site.


Along with diathermy, ultrasound was developed in the 1950s.15 By use of a crystalline-bonded applicator, electromagnetic energy is converted to sound waves that penetrate and heat deep tissues. Ultrasound waves are non-ionizing and have a high frequency above the range of the human ear. It can be administered in pulses or continuously.

Ultrasound has advantages over diathermy.15 It is less costly than diathermy, is portable, and has short treatment times ranging from 3 to 8 minutes. It has been reported to be effective in treating many types of inflammatory conditions including tendinitis, bursitis, tenosynovitis, muscle spasms, epicondylitis and arthritis. It promotes some reabsorption of blood and lymph products sequestered in the pain site.15 One of its greatest attributes is that it very effectively delivers pharmaceuticals, including corticoids, lidocaine, and opioids,10-12 to the pain site—providing it is not too deep below the skin surface. As mentioned previously, this process is called phonophoresis.

Last updated on: November 13, 2012