The efficacy of un-united tibial fracture treatment
using pulsing electromagnetic fields: relation to biological activity on
non-union bone ends.
Ultrastructural study of hyaluronic acid before and after
the use of a pulsed electromagnetic field, electrorydesis, in the
treatment of wrinkles.
Optimization of electric field parameters for the control
of bone remodeling: exploitation of an indigenous mechanism for the
prevention of osteopenia.
Pulsed magnetic fields improve osteoblast activity during
the repair of an experimental osseous defect.
Use of pulsed electromagnetic fields in treatment of
loosened cemented hip prostheses. A double-blind trial.
The effect of low-frequency electrical fields on
osteogenesis.
Treatment of ununited tibial fractures: a comparison of
surgery and pulsed electromagnetic fields (PEMF).
Long-term pulsed electromagnetic field (PEMF) results in
congenital pseudarthrosis.
Protection against focal cerebral ischemia following
exposure to a pulsed electromagnetic field.
The efficacy of un-united tibial fracture treatment
using pulsing electromagnetic fields: relation to biological activity on
non-union bone ends.
Thirty un-united tibial fractures with a median time since injury of
18+/-9 months were treated by electrical stimulation using pulsing
electromagnetic field therapy. Union was achieved in 25 cases (83.3%) in
a median interval of 8.6+/-3.2 months. Patient age, gender, the presence
of surgical hardware, length of disability, and the number of surgical
procedures did not affect the outcome. Un-united fractures that appeared
to be hypertrophic or sclerotic, indicating a good blood supply to the
bone ends, all healed.. Pulsing electromagnetic field therapy is an
effective treatment for un-united tibial fractures with good blood
supply to the bone ends.
Ito H. et.al. Department of Orthopaedic Surgery,
Nippon Medical School, Tokyo, Japan.
Ultrastructural study of hyaluronic acid before and
after the use of a pulsed electromagnetic field, electrorydesis, in the
treatment of wrinkles.
BACKGROUND. Treatment of wrinkles has become an increasing problem for
dermatologists. Hyaluronic acid is a component of the family of
glycosaminoglycans (GAGS, substances known for their property of
retaining water), that significantly decreases with aging and in
wrinkles. A new technique that uses a specific pulsed electromagnetic
field, electrorydesis, has been introduced in the treatment of wrinkles
associated with aging. The treatment is based on the reported in vitro
effects of specific electromagnetic fields on fibroblast cultures (e.g.,
an increase in DNA synthesis and in the production of collagen and
presumably also of GAGS). METHODS. The in vivo effects of the
electromagnetic field on aged skin (3 subjects aged 50, 56 and 60
years), with particular focus on the ultrastructural modifications and
GAGS amount before and after the treatment, were evaluated by electron
microscope. RESULTS. The ultrastructural study (tissue stained with
alcian blue) showed after treatment a significant increase (p < 0.005)
of the electron-dense granules (corresponding to hyaluronic acid),
located in collagen elastic fibers, and in the soluble matrix. This
presumably leads to subsequent edema that was clinically evident after
the treatment. CONCLUSIONS. These data suggest that the increased levels
of GAGS and the subsequent edema of the dermis could explain at least in
part the clinical changes observed after electrorydesis treatment (e.g.,
swelling and "disappearance" of the wrinkle).
Ghersetich I. Et.al. De. of Dermatology, University
of Florence, Italy. Int J Dermatol
Optimization of electric field parameters for the
control of bone remodeling: exploitation of an indigenous mechanism for
the prevention of osteopenia.
The discovery of piezoelectric potentials in loaded bone was
instrumental in developing a plausible mechanism by which functional
activity could intrinsically influence the tissue's cellular environment
and thus affect skeletal mass and morphology. Using an in vivo model of
osteopenia, we have demonstrated that the bone resorption that normally
parallels disuse can be prevented or even reversed by the exogenous
induction of electric fields. Importantly, the manner of the response
(i.e., formation, turnover, resorption)
is exceedingly sensitive to subtle changes in electric field parameters.
Fields below 10 microV/cm, when induced at frequencies between 50 and
150 Hz for 1 h/day, were sufficient to maintain bone mass even in the
absence of function. Reducing the frequency to 15 Hz made the field
extremely osteogenic. Indeed, this frequency-specific sinusoidal field
initiated more new bone formation than a more complex pulsed
electromagnetic field (PEMF), though inducing only 0.1% of the
electrical energy of the PEMF. The frequencies and field intensities
most effective in the exogenous stimulation of bone formation are
similar to those produced by normal functional activity. This lends
strong support to the hypothesis that endogenous electric fields serve
as a critical regulatory factor in both bone modeling and remodeling
processes. Delineation of the field parameters most effective in
retaining or promoting bone mass will accelerate the development of
electricity as a unique and site-specific prophylaxis for osteopenia.
Because fields of these frequencies and intensities are indigenous to
bone tissue, it further suggests that such exogenous treatment can
promote bone quantity and quality with minimal risk or consequence.
Rubin C. Et.al. Dep. Orthopaedics, State University
of New York J Bone Miner Res
Pulsed magnetic fields improve osteoblast activity
during the repair of an experimental osseous defect.
The influence of pulsed low-frequency electromagnetic fields (PEMFs) on
bone formation was investigated in studies of the healing process of
transcortical holes, bored at the diaphyseal region of metacarpal bones
of six adult horses, exposed for 30 days to PEMFs (28 G peak amplitude,
1.3 ms rise time, and 75 Hz repetition rate). A pair of Helmholtz coils,
continuously powered by a pulse generator, was applied for 30 days to
the left metacarpal bone, through which two holes, of equal diameter and
depth, had been bored at the diaphyseal region. Two equal holes, bored
at the same level in the right metacarpal and surrounded by an inactive
pair of Helmholtz coils, were used as controls. All horses were given an
intravenous injection of 25-30 mg/kg of tetracycline chloride on the
15th and again on the 25th day after the operation and were killed 5
days later. The histomorphometric analysis indicated that both the
amount of bone formed during 30 days and the mineral apposition rate
during 10 days (deduced from the interval between the two tetracycline
labels) were significantly greater (p <0.01 and p < 0.0001,
respectively) in the PEMF-treated holes than in the controls. As did a
previous investigation, these preliminary findings indicate that PEMFs
at low frequency not only stimulate bone repair but also seem to improve
the osteogenic phase of the healing process, at least in our
experimental conditions.
Cane V. et.al. Institute of Human Anatomy,
University of Modena, Italy. : J Orthop Res
Use of pulsed electromagnetic fields in treatment of
loosened cemented hip prostheses. A double-blind trial.
A double-blind trial of pulsed electromagnetic fields (PEMFs) for
loosened cemented hip prostheses was conducted at two centers. Of the 40
patients who enrolled, 37 met entry criteria and were available for
analysis. All patients completed six months of treatment (either active
or control units). Success was determined clinically by a Harris hip
score greater than or equal to 80 points (or an increase of ten points
if initially greater than or equal to 70 points). Ten of the 19 active
units were successes (53%), whereas two of the 18 controls (11%)
exhibited a placebo effect, a statistically significant and clinically
relevant result. A 60% relapse rate among the active successes was seen
at 14 months poststimulation, and despite maintenance therapy of one
hour per day, the relapse rate increased to 90% at three years. These
data suggest that for loosened cemented hip prostheses, use of PEMFs is
a treatment option to delay revision hip surgery.
Kennedy W. et.al. Theda Clark Regional Medical
Center, Wisconsin. Clin Orthop
The effect of low-frequency electrical fields on
osteogenesis.
An in vivo animal model of disuse osteopenia was used to determine the
osteogenic potential of specific components of electrical fields. The
ability of a complex pulsed electrical field to inhibit loss of bone was
compared with the remodeling response generated by extremely low-power,
low-frequency (fifteen, seventy-five, and 150-hertz) sinusoidal
electrical fields. The left ulnae of thirty adult male turkeys were
functionally isolated by creation of distal and proximal epiphyseal
osteotomies and then were exposed, for one hour each day, to an
electrical field that had been induced exogenously by means of magnetic
induction. After a fifty-six-day protocol, the remodeling response was
quantified by a comparison of the cross-sectional area of the mid-part
of the diaphysis of the functionally isolated ulna with that of the
intact contralateral ulna. Disuse resulted in a 13 per cent mean loss of
osseous tissue, which was not significantly different than the 10 per
cent loss that was caused by disuse treated with inactive coils.
Exposure to the pulsed electrical fields prevented this osteopenia and
stimulated a 10 per cent mean increase in the bone area. The osteogenic
influence of the sinusoidal electrical fields was strongly dependent on
the frequency; the 150, seventy-five, and fifteen-hertz sinusoidal
fields, respectively, generated a -3 per cent, + 5 per cent, and + 20
per cent mean change in the bone area. These results suggest a tissue
sensitivity that is specific to very low-frequency sinusoidal electrical
fields and they imply that the induced electrical fields need not have
complex waveforms to be osteogenic. Since the frequency and intensity
range of the sinusoidal fields producing the greatest osteogenic
response are similar to the levels produced intrinsically by normal
functional activity, these results support the hypothesis that
electricity plays a role in the retention of the normal remodeling
balance within mature bone.
McLeod K. et.al. Dep. Orthopaedics, School of
Medicine, State University of New York, : J Bone Joint Surg Am
Treatment of ununited tibial fractures: a comparison
of surgery and pulsed electromagnetic fields (PEMF).
The use of pulsed electromagnetic fields (PEMF) is gaining acceptance
for the treatment of ununited fractures. The results of 44 articles
published in the English language literature have been compiled to
assess the effectiveness of PEMF vs surgical therapy. For ununited
tibial fractures, 81% of reported cases healed with PEMF vs 82% with
surgery. After multiple failed surgeries, the success rate of PEMF is
reported to be greater than with surgery; this discrepancy increases
with additional numbers of prior surgeries. In infected nonunions, the
results of surgical treatment decreased by 21% and were less than the
results utilizing PEMF (69% vs 81%). In open fractures, surgical healing
exceeded PEMF (89% vs 78%), whereas in closed injuries PEMF cases healed
more frequently (85% vs 79%). In general, PEMF treatment of ununited
fractures has proved to be more successful than noninvasive traditional
management and at least as effective as surgical therapies. Given the
costs and potential dangers of surgery, PEMF should be considered an
effective alternative. Experience supports its role as a successful
method of treatment for ununited fractures of the tibia.
Gossling H. Et.al. Dep. Orthopedic Surgery,
University of Connecticut Orthopedics
Long-term pulsed electromagnetic field (PEMF)
results in congenital pseudarthrosis.
Ninety-one patients with congenital pseudarthrosis of the tibia have
been treated with pulsed electromagnetic fields (PEMFs) since 1973 and
all except 4 followed to puberty. Lesions were stratified by
roentgenographic appearance. Type I and type II had gaps less than 5 mm
in width. Type III were atrophic, spindled, and had gaps in excess of 5
mm. Overall success in type I and II lesions was 43 of 60 (72%). Of
those 28 patients seen before operative repair had been attempted, 7 of
8 type I lesions healed (88%), whereas 16 of 20 type II lesions healed
(80%) on PEMFs and immobilization alone. Only 19% (6 of 31) type III
lesions united, only one of which did not require surgery. Sixteen of 91
limbs (18%) were ultimately amputed, most before treatment principles
were fully defined in 1980. Fourteen of these 16 patients (88%) had type
III lesions. Refracture occurred in 22 patients, most as the result of
significant trauma, in the absence of external brace support. Twelve of
the 19 refractures, retreated with PEMFs and casts, healed on this
regime. Episodic use of PEMFs proved effective in controlling stress
fractures in several patients until they reached puberty. PEMFs, which
are associated with no known risk, appear to be an effective,
conservative adjunct in the management of this therapeutically
challenging, congenital lesions.
Bassett C. et.al. Bioelectric Research Center,
Riverdale, New York Calcif Tissue Int
Protection against focal cerebral ischemia following
exposure to a pulsed electromagnetic field.
There is evidence that electromagnetic stimulation may accelerate the
healing of tissue damage following ischemia.. Exposure to pulsed
electromagnetic field attenuated cortical ischemia edema on MRI at the
most anterior coronal level by 65% (P < 0.001). On histologic
examination, PEMF exposure reduced ischemic neuronal damage in this same
cortical area by 69% (P < 0.01) and by 43% (P < 0.05) in the striatum.
Preliminary data suggest that exposure to a PEMF of short duration may
have implications for the treatment of acute stroke.
Grant G. et.al. Department of Neurosurgery, Stanford
University, California
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