| BC Medical Journal Volume 43, Number 10,
December 2001, pages 573-577 |
Alleviation of pain
with the use of Farabloc, an electromagnetic shield: A review
Two studies have
shown that Farabloc reduces pain in human subjects who suffer
from phantom limb pain or delayed onset muscle soreness, but
the mechanism is unknown.
D.B. Clement, MD and J.E. Taunton, MD
Dr Clement is
a professor emeritus and Dr Taunton is a professor in the
Division of Sports Medicine, Department of Family Practice,
Faculty of Medicine, University of British Columbia.
Contents
Abstract
Introduction
Phantom limb pain
Outcome measures
Statistical
analysis
Results
Discussion
Delayed onset muscle
soreness
Outcome measures
Statistical
analysis
Results
Discussion
Conclusion
References
Abstract
Objective:
Review the research on the alleviation of pain by Farabloc,
a fabric with electromagnetic shielding properties.
Data source and
selection: Review the results of two studies on the efficacy
of Farabloc on phantom limb pain and delayed onset muscle
soreness in human subjects:
Conine TA, Hershler
C, Alexander SA, et al. The efficacy of Farabloc in the treatment
of phantom limb pain. Can J Rehab 1993;6:155.
Zhang J, Clement DB,
Taunton JE. The efficacy of Farabloc, an electromagnetic shield
in attenuating delayed onset muscle soreness. Clin J Sport
Med 2000;10:15-21.
Main results:
The placebo-controlled double-blind cross-over study demonstrated
reduced phantom limb pain when using double layers of Farabloc
covering the stump of the amputated limb. The placebo-controlled
single-blind cross-over study on delayed onset muscle soreness
demonstrated reduced pain, less loss of muscle strength, and
reduced blood markers of inflammation.
Conclusion:
Farabloc fabric, which is demonstrated to have electromagnetic
shielding properties when covering the stump of an amputated
limb or when wrapped around the thigh muscle perturbed by
delayed onset muscle soreness, significantly reduces pain
in human subjects.
[Contents]
Introduction
Farabloc was devised by
Frieder Kempe in 1978 in an effort to relieve phantom limb
pain experienced by a family member. Initial work by G.L.
Bach reported beneficial effects on phantom limb pain and
later suggested that Farabloc may also reduce rheumatic pain
(unpublished report, 1990).
Farabloc is a fabric made of a woven
mesh of stainless steel and nylon thread and has been proven
to have electromagnetic shielding properties (S. McDiarmid
and M. Trudeau, unpublished report, 1998). The fabric is made
of 9.5% steel wire consisting of iron, nickel, and chromium.
Farabloc was found to block electromagnetic fields four times
more effectively than placebo fabric, and to be an effective
electromagnetic shield at frequencies greater than 1 MHz.
It has been suggested that Farabloc has limited shielding
effects on electromagnetic radiation in the low-frequency
electromagnetic field (EMF), particularly the very low-frequency
(<10 KHz), extremely low-frequency, and super and extremely
high-frequency range (>10,000 MHz). Farabloc is most effective
in shielding against EMF in the high- and ultrahigh-frequency
range characteristic of radio frequency.
A variety of studies have proposed
that the alteration of EMF has an effect on biologic systems.[1]
Alteration of EMF does not create pain in humans but Grundler[2]
and Eichwald and Walleczek[3]
have suggested that enzyme systems that are sensitive may
modulate calcium dynamics at a cellular membrane level with
changes in EMF. Sandyk[4]
performed a study in which patients with Parkinson’s symptoms
experienced an increase in central dopamine levels secondary
to extracerebral exposure to low-frequency EMF.
Detlavs[5]
demonstrated a greater inflammatory response in rats with
full thickness dermal wounds after exposure to modulated nonthermal
EMF. Valberg[6] postulated
a variety of mechanisms in which EMF may produce biological
effects. It is suggested that energy transfer by acceleration
of ions and charged proteins modifies cell membranes and receptor
proteins. Electric fields induced inside the body exert force
on electric charges and electric moments. The magnetic moments
of ferromagnetic particles and free radical molecules interact
with magnetic fields.[7]
Research has been conducted using EMF in extra low-frequency
range to enhance healing in bone fractures and cell metabolism.[1,8,9]
Anecdotal reports of relief by patients
suffering from phantom limb pain and decreased creatine phosphokinase
serum levels in horses after exercise when using Farabloc
prompted the initiation of randomized placebo-controlled studies.
Search of the literature at this time reveals only two controlled
studies. A review of these two studies follows in this article.
[Contents]
Phantom
limb pain
This distressing syndrome following
amputation affects the majority of individuals with healed
stumps.[10] It
is characterized by a cramping, stabbing, or crushing sensation
in the missing extremity, which may be of an episodic or continuous
nature.
A multitude of treatments for this
condition were investigated including neurosurgical, pharmacological,
physical, and psychological treatments. None were found to
be more successful in the control of phantom limb pain than
placebo.[11]
Thirty-four patients with amputation
of either the lower or upper extremity, all with complaints
of phantom limb pain, were divided into two groups in a randomized
double-blind cross-over design and treated with either Farabloc/placebo
or placebo/ Farabloc fabric fitted over the stump. At least
a double thickness of fabric was used for more than 4 hours
per day. Patients were excluded who had stump complications,
compensation involvement, prosthetic fitting complications,
or neuropsychological problems. Of the total, 24 patients
had loss of a lower extremity, while the remaining 10 had
upper extremity amputations. There was no restriction of any
other therapy including drugs or physiotherapy during the
period of study, as previous research showed none to be effective.
[Contents]
Outcome
measures
Pain was evaluated by the use of
a visual analog scale (VAS). The zero point on a 10 cm line
represented “no pain relief” and the other extreme represented
“complete pain relief.”[12]
VAS was measured at the outset, the end of the first phase,
after the crossover and washout period, and at the conclusion
of the study.
Statistical
analysis
Repeated measures analysis of variance
and Tukey’s multiple pairwise comparison range test were used
to analyze the results. Significance was set at p<0.01
and p<0.05 respectively.
Results
Pain was significantly reduced in
the Farabloc group compared to the placebo group as shown
in Table 1 (p<.001).
The pretreatment, placebo, and Farabloc means shown in Table
2 demonstrate a significant effect on pain reduction
by Farabloc (p<.05).
Discussion
The greatest pain relief in the 34
subjects occurred during the period when double layers of
Farabloc covered the stump of the amputated extremity.[13]
Nine of the subjects reported pain relief of greater than
5 points on the VAS scale, while the average relief was measured
at 3 points. One subject reported increased pain while using
Farabloc. The nature of the study does not allow for any explanation
of these positive results.
[Contents]
Delayed
onset muscle soreness
Stimulated by the positive conclusions
from the study of phantom limb pain and previous observation
of reduced serum creatine phosphokinase in horses after exercise,
a study to evaluate the use of Farabloc on a muscle injury
model using human subjects was undertaken.[14]
The common feature of muscle injury and phantom limb pain
is the quest for analgesia. The etiology of the pain is not
similar in each condition.
The muscle injury model used was
created by 37 minutes of eccentric knee extension consisting
of 20 sets of 10 repetitions with 10 seconds of recovery between
sets using a Biodex dynamometer. This created delayed onset
muscle soreness that produced pain and strength loss secondary
to muscle damage for 5 to 7 days. A randomized single-blind
placebo-controlled crossover design was used (Figure
1).
Twenty untrained volunteers (10 men
and 10 women) ranging in age from 20 to 38 years were recruited
using specific inclusion and exclusion criteria. Research
protocol was approved by the University of BC Screening Committee
for Research Involving Human Subjects.
Farabloc or placebo fabric was wrapped
in double layers around the right thigh of each subject for
5 days immediately following the eccentric work.
[Contents]
Outcome
measures
Muscle soreness was evaluated by
use of a VAS and eccentric torque of the knee extensors measured
with the Biodex Dynamometer daily for 5 days. Serum indices
of muscle damage were selected for serial assessment five
times in the first 48 hours. Creatine phosphokinase and myoglobin
are indicative of muscle cell membrane disruption.[15,16]
Malondialdehyde is an index of lipid peroxidation that is
increased in the process of free radical damage secondary
to severe eccentric induced muscle stress.[17]
Since white blood cells are known to increase with severe
exercise and muscle damage as a sign of inflammatory response,
leukocytes and neutrophils were assessed.
Statistical
analysis
A repeated measures factorial analysis
of variance was performed on the combined data from the 20
participants for all seven variables in the two stages. Significance
was set at p=<0.01.
Results
VAS and eccentric torque of the knee
are shown in Figure
2 with significantly different results (p=0.00) and
(p=0.003) respectively between Farabloc and placebo. Malondialdehyde
(Figure
3), creatine phosphokinase, myoglobin, (Figure
4), white blood cells, and neutrophils (Figure
5) again showed significant results (p=0.000, p=0.000,
p=0.000 and p=0.008) respectively between Farabloc and placebo
fabric.
Discussion
Double layers of Farabloc fabric
wrapped around the thigh of human subjects after eccentric
exercise demonstrates attenuation of symptoms, signs, and
muscle inhibition associated with delayed onset muscle soreness.
There was statistically significant reduction in pain and
a reduction in loss of strength when Farabloc was used immediately
after exercise compared to placebo.
The magnitude of these results suggest
a substantial clinical reduction in post-exercise disability.
These results are consistent with the finding in the study
of phantom limb pain. Pain reduction of approximately 3 points
on the VAS scale was surprisingly similar in both studies.
Lower pain and higher peak torque with the use of Farabloc
compared to placebo suggests that muscle damage is limited
in some manner but does not identify a mechanism by which
the effect occurs. The reduced malondialdehyde response with
the use of Farabloc is consistent with reducing free radical
damage and reduced lipid peroxidation. Reductions of creatine
phosphokinase and myoglobin are consistent with the possibility
that Farabloc stabilizes the muscle cell membrane and reduces
the escape of these substances into the serum. All muscular
activity will create some increase in creatine phosphokinase
levels. The more severe and uncommon the muscular activity,
the higher the level of muscle cell disruption and the subsequent
serum levels of creatine phosphokinase. Pain or stiffness
in the muscle group is more likely to occur when the level
of exercise is unaccustomedly high.
[Contents]
Conclusion
Farabloc, an electromagnetic shielding
fabric, reduces pain in human subjects who suffer from phantom
limb pain or delayed onset muscle soreness when assessed in
placebo-controlled cross-over designed studies. The mechanism
behind these observations is not known. Other authors have
speculated that alteration in EMF may have biological effects
secondary to stabilization of the cell membrane and enhancement
of antioxidant properties. This could explain the reduced
levels of anti-inflammatory markers in the delayed onset muscle
soreness study. Alteration of EMF by shielding from high-frequency
exposure could alter the permeability of the cell membrane,
and the subsequent reduced transfer of ions may stabilize
the cell’s response to excess exercise. Neither study reported
any negative observations or side effects.
Clearly these results require much
greater study as the potential application of an external
fabric that has protective and anti-inflammatory properties
may have broad clinical application in a wide variety of conditions.
[Contents]
Table 1. The result of the repeated
measures analysis of variance comparing the difference in
the Visual Analog Scale mean scores for each period by two
groups.
|
Source
|
D.F.
|
Sum of squares
|
F-value
|
p
|
|
Group
Period
Group x period
Subjects
Error
TOTAL
|
1
3
3
32
96
135
|
1.76
106.84
50.83
222.17
211.46
593.06
|
0.25
16.17
7.69
-
-
-
|
0.6237
0.0000
0.0001
-
-
-
|
Table 2. The mean and standard deviation
values for the Visual Analog Scale scores for the four periods:
pretreatment, Farabloc-placebo group 1, placebo-Farabloc group
2, washout, and alteration of treatment.
| |
PERIOD
|
|
Pretreatment
Mean (sd)
|
Farabloc-placebo group 1, placebo-Farabloc group 2
Mean (sd)
|
Washout
Mean (sd)
|
Alteration of treatment
Mean (sd)
|
Group 1
Group 2 |
1.22 (1.08)
1.31 (0.90)
|
3.96 (2.75)
2.43 (1.93)
|
1.54 (1.04)
1.99 (1.30)
|
2.36 (1.28)
4.27 (3.12)
|
[Contents]
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[Contents]
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