Modulation of bone loss during disuse by pulsed
electromagnetic fields.
Treatment of chronic varicose ulcers with pulsed
electromagnetic fields: a controlled pilot study.
Low energy high frequency pulsed electromagnetic therapy
for acute whiplash injuries. A double blind randomized controlled study.
Bone density changes in osteoporosis-prone women exposed to
pulsed electromagnetic fields (PEMF).
Effect of pulsed magnetic fields on human umbilical
endothelial vein cells
Effects of pulsed magnetic fields in the therapy of
osteoporosis induced by ovariectomy in the rat.
Possible therapeutic applications of pulsed magnetic fields
The Canadian experience with pulsed magnetic fields in the
treatment of un-united tibial fractures
Modulation of bone loss during disuse by pulsed
electromagnetic fields.
The effect of pulsed electromagnetic fields (PEMFs) on bone loss
associated with disuse was investigated by applying 1.5 Hz repetitions
of 30 ms bursts of asymmetric pulses, varying from +2.5 to -135 mV, to
bones deprived of their normal functional loading. The proximal portion
of one fibula in each of a group of ovariectomised adult female beagle
dogs was isolated from functional loading in vivo by proximal and distal
osteotomies. Comparison of these prepared bones with their intact
contralateral controls after 12 weeks, showed a 23% reduction in
cross-sectional area. In similarly prepared bones exposed to PEMFs for 1
h per day, 5 days per week, this bone loss was substantially and
significantly reduced to 9% (p = 0.029). There was no evidence of any
new bone formation on the periosteal surface of prepared fibulae in
treated or untreated situations. PEMF treatment was not associated with
any significant change in number of osteons per mm2 formed within the
cortex of the bones, their radial closure rate, or their degree of
closure. The modulation in loss of bone area associated with exposure to
PEMFs can, therefore, be inferred to be due to a reduction in resorption
on the bone surface.
Skerry T. et.al. Dep. of Anatomy, University of
Bristol, U.K. J Orthop Res
Treatment of chronic varicose ulcers with pulsed
electromagnetic fields: a controlled pilot study.
To evaluate the efficacy of pulsed electromagnetic fields (PEMF) in
healing of chronic varicose ulcers, 19 patients with this condition were
included in a double-blind controlled clinical trial. All patients
received standard ulcer therapy throughout the duration of the study and
were randomly divided into two groups to receive either active or
inactive PEMF therapy. Active therapy was provided by the use of a pait
of Helmholtz coils on a twice weekly basis over a five week period and
inactive therapy was provided on an identical regimen with identical
coils wound so that no magnetic field was produced when an electric
current was passed through them. The clinician and patients were unable
to distinguish the active or inactive coils. No statistically relevant
difference was noted between the two groups in the healing rates of the
ulcer, change in the lower leg girth, pain or infection rates. However
there was a trend in favour of a decrease in ulcer size and lower leg
girth in the group treated with active PEMF. As PEMF is a novel
treatment for chronic varicose ulcers, more work needs to be done to
establish treatment parameters and its usefulness in the treatment of
this condition.
Todd D. et.al. Dep. Dermatology, Belfast City
Hospital. Ir Med J
Low energy high frequency pulsed electromagnetic
therapy for acute whiplash injuries. A double blind randomized
controlled study.
The standard treatment of acute whiplash injuries (soft collar and
analgesia) is frequently unsuccessful. Pulsed electromagnetic therapy
PEMT has been shown to have pro-healing and anti-inflammatory effects.
This study examines the effect of PEMT on the acute whiplash syndrome.
PEMT as described is safe for domiciliary use and this study suggests
that PEMT has a beneficial effect in the management of the acute
whiplash injury.
Foley-Nolan D. et.al. Mater Hospital, Dublin,
Ireland.
Bone density changes in osteoporosis-prone women
exposed to pulsed electromagnetic fields (PEMF).
To determine the effect of a 72 Hz pulsating electromagnetic field
(PEMF). Bone mineral densities of the treated radii measured by
single-photon densitometry increased significantly in the immediate area
of the field during the exposure period and decreased during the
following 36 weeks. The data suggest that properly applied PEMF, if
scaled for whole-body use, may have clinical application in the
prevention and treatment of osteoporosis.
Tabrah F. et.al. University of Hawaii School of
Medicine, Honolulu.
Effect of pulsed magnetic fields on human umbilical
endothelial vein cells
The long-term goal of this program was to examine the efficacy of
electromagnetic fields as an adjunct therapy to facilitate wound repair.
The experiments reported here were directed to the question of whether
pulsed electromagnetic fields (PEMF) could facilitate endothelial cell
migration following induction of a wound. These studies were based on a
report that weak PEMF facilitated cell migration in a wounded confluent
monolayer culture of human umbilical vein cells. Experiments reported in
this paper were an attempt to reproduce and extend these observations.
Our data support the original observations. Further, we examined several
hypotheses in an attempt to clarify the mechanism of interaction between
the applied electromagnetic fields and cells. The data do not support
the hypothesis that PEMF is acting in a manner similar to endothelial
cell-growth factor, a normal component of the growth medium, or that
PEMF applied at the time of cell transfer enhance DNA replication. We
have found that PEMF is more effective in accelerating migration if they
induce an electric field that is perpendicular rather than parallel to
the sides of the wound.
Goodman, E. et.al J. Biomedical Res. Inst., Univ.
Wisconsin, WI, USA
Effects of pulsed magnetic fields in the therapy of
osteoporosis induced by ovariectomy in the rat.
This paper presents preliminary results on the effects of pulsed
electromagnetic fields (EMF) in the therapy of post menopausal
osteoporosis induced by ovariectomy in female rats aged ten months. In
particular, the effects of the intensity of pulsed EMF applied at
constant frequency has been studied. Magnetic fields pulsed at 50 Hz
were used having a positive sinusoidal wave form with a maximum
intensity of 30 and 70 Gauss. Treatment lasting one hour per day for 4
months showed that the pulsed EMF with 30 Gauss of maximum intensity are
able to slow down the bone mass loss, keeping it within some 10%; with
pulsed EMF with 70Gauss of maximum intensity, instead, no significant
bone mass loss was observed.
Zati, A.et.al. Institute Orthopaedic Rizzoli,
University of Bologna.
Possible therapeutic applications of pulsed magnetic
fields
Magnetotherapy is a relatively new, nowadays however, relatively
widespread method in several medical disciplines. The mechanism proper
of the favorable action of the pulsed magnetic field on the living
organism is not quite clear so far, clinical investigations revealed,
however, a favorable anti-inflammatory, angioedematous and analgesic
therapeutic effect. The authors sought an optimal frequency of the
pulsed magnetic field with regard to the character of the disease. They
focused attention above all on treatment of acute and chronic
inflammatory conditions of the locomotor apparatus, ischaemia of the
blood vessels of the lower extremities, dyspeptic syndrome, lactation
mastitis and other diseases. One therapeutic cycle lasted 20 minutes,
the mean number of cycles varied between 5.8 and 7.7. A regression of
complaints was recorded as a rule after 2-3 sessions. The optimal
frequency of the pulsed magnetic field seems to be a value between 10.0
and 25.0 Hz. It is useful in particular in severe conditions to
repeat the therapeutic cycle after 2-3 months. The advantage of this
therapeutic method is the minimal number of contraindications.
Navratil, L. et.al. Czech Republic
The Canadian experience with pulsed magnetic fields
in the treatment of un-united tibial fractures
A clinical survey of 56 patients was conducted at four different centers
in Canada to evaluate the effect of extremely low frequency pulsed
magnetic fields (PMF) on un-united fractures of the tibia. All ten
patients with delayed union and 84% of the 44 patients with non-union
healed. One case with a traumatic pseudarthrosis and one with a
congenital pseudarthrosis failed to respond to treatment. These results
compare favorably to those reported by others using a system with
different pulse characteristics. Prolonged immobilization is necessary
and poses problems of rehabilitation. Non-unions with a gap between the
tibial fragments and pseudarthroses are better treated with bone
grafting and internal fixation prior to electrical stimulation.
Haas, W. et.al. J. of Clin. Orthop.
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