Collected Case Report
Methods:
Seventy-seven patients were selected for review from pain clinic charts according to their diagnostic code indicating neuropathic pain. Patients included in this paper had sensory examinations and reflexes altered from normal and a mechanism of injury that could reasonably have caused neuropathic pain. Patients who did not have pretreatment and posttreatment data for every visit, or who met criteria for other diagnoses (eg, fibromyalgia, diabetic peripheral neuropathy, postherpetic neuralgia) were excluded. Twenty patients met criteria and were included in the analyses. Sixteen (80%) were females and 4 (20%) were males. The average age was 47.70 (SD=11.19, range 24 to 68).
Treatment Method:
FSM can be applied using any 2-channel microampere current device that can provide frequency pulses accurate to 3 digits on 2 channels simultaneously using alternating or polarized positive DC current with a ramped square wave pulse. Two different devices were used to deliver treatments. The Precision Micro (Precision Microcurrent, Newberg, Oregon), an analog, battery-operated 2-channel,
3-digit-specific microcurrent device was used for some THE PAIN PRACTITIONER | VOLUME 20, NUMBER 3 | 69 treatment sessions. This device requires frequencies on both channels to be set and changed manually. The AutoCare, or AutoCare Plus (Microcurrent Technologies, Seattle, Washington) was used during some treatments. These are digital, battery-operated, 2-channel, 3-digit specific microcurrent devices preprogrammed to run certain specific frequency combinations for various time periods. They include the protocols for treating neuropathic pain. Patients must be adequately hydrated for the treatment to be effective. In general, patients were instructed to drink 1 to 2 quarts of water in the 3 to 4 hours before treatment.
For treatment, the patients were placed in a comfortable, supported position appropriate to the nerve root being treated. The graphite glove electrodes were wrapped in a warm, wet hand towel to allow broad flexible skin coverage and good conductivity (Figure 1). The positive contact was placed at the point on the spine where the nerve exits. The negative contact was placed at the distal end of the nerve to be treated and the current was polarized positive. The frequencies observed to reduce pain were 40Hz on one channel and 396 Hz on the second channel. The pain begins dropping in minutes and declines in a time-dependent fashion over 30 minutes, requiring a maximum of 60 minutes to reach optimal benefit. Treatment beyond 60 minutes did not produce any additional improvement. Once the pain was reduced, attempts to return to full range of motion were observed to create pain or sensations of pulling or aching in the affected nerve root. Adhesions between nerves and the surrounding fascia and between the nerve, cord, and dura are known to cause pain and limit range of motion (11,12). Burn patients with mature scarring were treated with certain frequency combinations and experienced lasting increases in range of motion (13). Postradiation scarring was modified and range of motion increased by use of an impedancecontrolled, frequency-modulated microcurrent device (14).
Trial and error showed that if the patient was treated with the frequencies 13Hz on one channel and 396 Hz on the second channel while moving the limb (and nerve) to edge of the range, within the limits of comfort, the range of motion would return to normal within 10 to 15 minutes. Only this frequency combination was useful for increasing range of motion (Figure 2). The 40Hz and 396Hz combination had no effect on increasing range of motion and was useful only for reducing pain. 13Hz and 396 Hz had no effect on reducing pain and were useful only for increasing range.
In general, patients were treated twice weekly. Lowvelocity spinal manipulation was used after the microcurrent treatment in some, but not all patients. Side Effects
No patients reported or complained of side effects either during or after treatment. The most common side effect is a sensation of euphoria, presumably created by increases in endorphins, such as those seen in the fibromyalgia patients (8). It was not uncommon for patients to fall asleep during the first treatment, but no patient complained about this euphoric effect. Patients were kept in the clinic after treatment until they returned to normal and they were considered safe to drive.
If patients have bony foraminal or spinal cord stenosis, the current and treatment protocol may cause a
temporary increase in pain that resolves over 24 hours when the treatment is stopped. No increase in pain was observed in any of the patients in this analysis.
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Figure 1. Positive leads are placed where the treated nerve exits the spine. Negative leads are placed at the end of the dermatome. The leads are connected to graphite gloves and the graphite gloves are wrapped in a warm, wet contact to allow coverage and convenient placement. This placement treats the C5-C6-C7-C8 nerve roots. Figure 2. When the pain is reduced and range of motion is still restricted, the frequencies are set to 13Hz and 396Hz, and the affected nerve root and limb are moved gently through range of motion. When the patient reports pressure or discomfort, the limb is returned to neutral while the current and frequency continue to treat. The range is tested again and usually increases with each attempt. Normal range is usually achieved within 15 minutes.
Results:
The chronicity of neuropathic pain varied from 1 week to 44 years, with a mean of 6.69 years (SD=10.72). Patients received an average of 4.60 treatments, with a range from 1 to 15 (SD=3.75) treatments. The primary mechanism of pain most commonly reported was a disc injury (65%, n=13). Other mechanisms included traction injuries (n=2), falls (n=1), other (n=1), and unknown (n=1). Eleven patients had more than one mechanism of onset. Of those, 7 (35%) indicated a motor vehicle accident as the onset. No patient in this group had a lawsuit pending related to an accident. In general, patients with disc injuries required the greatest number of treatments; patients with
traction injuries required the fewest number of treatments. Table 1 provides the means and standard deviations for pretreatment and posttreatment pain scores for treatments 1 through 4. The Wilcoxon Signed Ranks Test was employed to compare patients’ pretreatment and posttreatment pain scores. Since the average number of treatments was 4.60, and 6 or fewer patients completed treatment 5 and beyond, analyses were completed only for treatments 1 through 4.
For treatment 1, the average initial pain score was 6.78 / 10 (SD= 1.80), with a range of 4 to 10. The average pain score at the end of the first treatment was 1.83 / 10 (SD=2.10), with a range from 0 to 8. Even with the outlier whose pain was reduced only from 10/10 to
8/10, the posttreatment pain scores were significantly lower than pretreatment scores with Z= -3.83 and p<0.001.
For treatment 2, the mean pretreatment pain score was 4.75 / 10 (+/- 2.60) and the mean posttreatment score was 0.97/ 10 (SD = 1.6). The posttreatment pain scores were significantly lower than pretreatment scores with Z = -3.63 and p<0.001.
For treatment 3, the mean pretreatment pain score was 5.14/10 (SD = 1.99) and the mean posttreatment pain score was 0.46 / 10 (SD = 0.84). Posttreatment scores were significantly lower than pretreatment scores, with Z = -3.30 and p<0.01.
For treatment 4, the mean pretreatment score was 3.94/10 (1.96) and the mean posttreatment score was 0.29/10 (SD = 0.76). The posttreatment scores were significantly lower, with Z = -2.37, and p<0.05. Of the 20 patients reviewed, 65% (n=13) fully recovered from nerve pain. Twenty-five percent terminated care before recovery (n=5) for reasons not associated with the treatment. One patient was referred for additional treatment by epidural steroid injection. One patient purchased a small automated microcurrent unit for home use while her disc injury healed.
Discussion
This retrospective analysis of a typical assortment of chronic neuropathic pain patients attempts to quantify the anecdotal reports of successful treatment of chronic neuropathic pain using frequency-specific microcurrent. Patients improve most dramatically during the first 4 treatments. Patients with traction injuries usually recover within 2 to 3 treatments. Patients with disc injuries and ligamentous laxity, especially in the cervical spine, require the greatest number of treatments because the discs and ligaments that are perpetuating the neuropathic pain need time, spinal stabilization exercises, and other forms of physical therapy to heal. All patients reported some reduction in pain with treatment. The patients who terminated care did so even after treatment had reduced pain and did so for reasons
not related to treatment side effects such as cost, travel time, and other personal situations. Only the frequencies 40 Hz on one channel and 396 Hz on the other channel reduced pain. Only the frequencies 13 Hz on one channel and 396 Hz on the other channel increased range of motion. As seen in the mouse trial and the fibromyalgia patients, patient response to the current and frequency combinations to reduce nerve pain were time dependent (8,10). Thirty to 60 minutes of treatment were required to reduce pain from an average of 6.78/10 to an average
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Table 1
Treatment # (n) Pre-Tx Mean (SD) Pre-Tx Range Post-Tx Mean (SD) Post-Tx Range
Treatment 1 (n=20) 6.78 (1.80) 4-10 1.83 (2.10) 0-8
Treatment 2 (n=17) 4.75 (2.56) 2-10 0.97 (1.60) 0-4 ………..
Treatment 3 (n=14) 5.14(1.99) 1-8 0.46 (.84) 0-2 ………..
Treatment 4 (n=7) 3.94 (1.96) 2-8 0.29 (.76) 0-2 ………..
of 1.83 /10 on a 0-10 VAS scale on the first treatment. Approximately 30 minutes of treatment were required to reduce pain from 4.75/10 to 0.97/10 for the second treatment. At the 15-minute mark, approximately half of the eventual effect was present. The 30- to 60-minute treatment time required to reduce neuropathic pain corresponds to the time-dependent response seen in the mouse anti-inflammatory research. In the mice, half of the effect was produced in 2 minutes and the full effect was seen at 4 minutes. Additional treatment time
beyond 4 minutes did not produce any additional effect (8). In neuropathic pain in humans, the pain begins to be reduced within a 15-minute treatment time, but 30 to 60 minutes are required to create optimal lasting reductions in pain. The frequencies to increase range of motion have their effect more quickly than those to reduce inflammation and pain but are still time dependent. The frequency must be
used for 10 to 15 minutes in combination with movement to produce an optimal increase in range of motion. Conclusion Dual channel, specific-frequency microamperage current produced dramatic improvements in a collected case report of patients with chronic neuropathic pain. Treatment is noninvasive, low risk, widely available, relatively inexpensive, and appears to have no significant side effects. A controlled trial should be performed to further evaluate its effectiveness in this otherwise difficult
patient group. ■
CAROLYN MCMAKIN, MA, DC, is the clinical director of the Fibromyalgia and Myofascial Pain Clinic of Portland, Oregon. She developed frequency specific microcurrent (FSM) in 1996. She maintains a part-time clinical practice, participates in research, and teaches seminars on the use of FSM. She has published five peer reviewed papers on the use of FSM in the treatment of myofascial pain, fibromyalgia, delayed onset muscle soreness, and shingles. She has lectured at the National Institutes
of Health and at numerous medical conferences in the US, England, Canada, and Australia, on the subjects of fibromyalgia, fibromyalgia associated with cervical trauma, and on the differential diagnosis and treatment of chronic pain syndromes. Her textbook titled Frequency Specific Microcurrent in Pain Management is in press with Elsevier to be released in 2010. Disclosure: No grants or financial recompense were involved in this case report. Carolyn McMakin is president of Frequency Specific Seminars, Inc.
Acknowledgements: The author wishes to acknowledge the assistance with data collection and analysis provided by Jessica Morea Irvine, MS and the advice and inspiration provided by Dr. David G Simons in the preparation of this article.
Correspondence: Carolyn McMakin, carolmcmakin(at)icloud.com
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