Effect of magnetic knee wrap on quadriceps strength in patients with symptomatic knee osteoarthritis.
Chen CY, Chen CL, Hsu SC, Chou SW, Wang KC.
Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Keelung, Taiwan.
OBJECTIVE: To determine the effects of magnetic knee wrap on
isokinetic quadriceps strength in patients with painful knee
osteoarthritis (OA).
DESIGN: Randomized, double-blinded, placebo-controlled and before-after trial.
SETTING: Rehabilitation clinic in a tertiary hospital.
PARTICIPANTS: Eligible patients (N=50) (mean age+/-SD, 66.0+/-8.6 y)
with mild to moderate knee OA were recruited from the outpatient
department and 37 (74%) completed the trial. Only 3 (6%) withdrew due to
study-related adverse effects.
INTERVENTIONS: Wearing the active (n=24) or sham (n=26) magnetic knee wrap for 12 weeks.
MAIN OUTCOME MEASURES: The primary outcome measure was isokinetic
quadriceps strength. Secondary outcome measures included the Health
Assessment Questionnaire Disability Index (HAQ-DI) and the Health
Assessment Questionnaire (HAQ) Pain Scale.
RESULTS: Using intention-to-treat analyses, the peak isokinetic
quadriceps strength increased significantly in the treated leg at 30
degrees/s (P=.007) and 60 degrees/s (P=.022) after wearing the magnetic
knee wrap. Compared with baseline, the median strength increase for the
treated leg in the study group significantly exceeded that in the
control group at week 4 (.05 Nm/kg vs -.09 Nm/kg at 60 degrees/s,
P=.038) and week 12 (30 degrees/s, .09 Nm/kg vs .04 Nm/kg, P=.044; 60
degrees/s, .17 Nm/kg vs .02 Nm/kg, P=.031).
The HAQ-DI and HAQ Pain Scales improved significantly in both groups.
Compared with baseline, the improvement at week 12 in terms of the
HAQ-DI in the study group significantly exceeded that in the control
group.
CONCLUSIONS: Magnetic knee wrap may significantly facilitate
isokinetic quadriceps strength in patients with mild to moderate knee OA
(osteoarthritis).
Chen CY, Chen CL, Hsu SC, Chou SW, Wang KC (Dec 2008). "Effect of
magnetic knee wrap on quadriceps strength in patients with symptomatic
knee osteoarthritis." Archives of Physical Medicine and Rehabilitation. 89(12):2258-64. PMID: 18976982
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Double-blind placebo-controlled trial of static magnets for the
treatment of osteoarthritis of the knee: results of a pilot study.
Wolsko PM, Eisenberg DM, Simon LS, Davis RB, Walleczek J, Mayo-Smith M, Kaptchuk TJ, Phillips RS.
Division for Research and Education, Harvard Medical School, Boston, MA, USA.
CONTEXT: Outpatient clinical studies of magnet therapy, a
complementary therapy commonly used to treat osteoarthritis (OA), have
been limited by the absence of a credible placebo control.
OBJECTIVE: Our objective was to assess the feasibility and promise of
studying static magnetic therapy for knee OA and determine the ability
of a new placebo-magnet device to provide concealment of group
assignment.
DESIGN: Randomized, double-blind, placebo-controlled clinical trial.
SETTING: Academic teaching hospital in Boston. PARTICIPANTS: We
enrolled 29 subjects with idiopathic or post-traumatic OA of the knee.
INTERVENTIONS: Subjects received either high-strength magnetic
(active) or placebo-magnetic (placebo) knee sleeve treatment for 4 hours
in a monitored setting and self-treatment 6 hours daily for 6 weeks.
MAIN OUTCOME MEASURE Primary outcomes were change in knee pain as
measured by the WOMAC Osteoarthritis Index Pain Subscale at 6 weeks and
extent of group concealment at study end.
RESULTS: At 4 hours, VAS pain scores (+/- SE) on a 5-item scale
(0-500, 500 worst) decreased 79 +/- 18 mm in the active group and 10 +/-
21 mm in the placebo group (P < 0.05). There were no significant
differences in any primary or secondary measure of efficacy between the
treatment groups at 6 weeks. Despite widespread testing for magnetic
properties, at study end, 69% of the active group and 77% of the placebo
group (P > 0.2) believed that they had been assigned to the active
treatment group.
CONCLUSION: Despite our small sample size, magnets showed statistically significant efficacy compared to placebo after 4 hours under rigorously controlled conditions.
The sustained efficacy of magnetic therapy for knee osteoarthritis
could be assessed in an adequately powered trial utilizing an
appropriate control such our new placebo-magnet device.
Alternative Therapies in Health and Medicine. 2004 Mar-Apr;10(2):36-43. PMID: 15055092
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Study on Application of Static Magnetic Field for Adjuvant Arthritis Rats
Norimasa Taniguchi11,3, Shigeyuki Kanai11,2, Masazumi Kawamoto2, Hiroshi Endo2 and Hideaki Higashino2 1Kansai College of Oriental Medicine Sennan-gun, Osaka, Japan, 2Department of Pharmacology, Kinki University School of Medicine Osaka-Sayama, Osaka, Japan, 3Department of Science, Pip-Fujimoto Co., Ltd Chuo-ku, Osaka, Japan
In order to examine the effectiveness of the application of static
magnetic field (SMF) on pain relief, we performed a study on rats with
adjuvant arthritis (AA).
60 female Sprague–Dawley (SD) rats (age: 6 weeks, body weight:
approximately 160 g) were divided into three groups [SMF-treated AA rats
(Group I), non-SMF-treated AA rats (Group II) and control rats (Group
III)]. The SD rats were injected in the left hind leg with 0.6 mg/0.05
ml Mycobacterium butyrium to induce AA. The rats were bred for 6 months
as chronic pain model. Thereafter, the AA rats were or were not exposed
to SMF for 12 weeks.
We assessed the changes in the tail surface temperature, locomotor
activity, serum inflammatory marker and bone mineral density (BMD) using
thermography, a metabolism measuring system and the dual-energy X-ray
absorptiometry (DEXA) method, respectively.
The tail surface temperature, locomotor activity and femoral BMD of
the SMF-exposed AA rats were significantly higher than those of the
non-SMF-exposed AA rats, and the serum inflammatory marker was
significantly lower.
These findings suggest that the pain relief effects are primarily due
to the increased blood circulation caused by the rise in the tail
surface temperature. Moreover, the pain relief effects increased with
activity and BMD of the AA rats.
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Effects of static magnets on chronic knee pain and physical function: a double-blind study.
Hinman MR, Ford J, Heyl H.
Department of Physical Therapy, University of Texas Medical Branch, Galveston, USA.
CONTEXT: Static magnets have become an increasingly popular
alternative therapy for individuals with musculoskeletal pain despite
limited scientific evidence to support their efficacy or safety.
OBJECTIVE: To determine the effects of static magnets on the pain and
functional limitations associated with chronic knee pain due to
degenerative joint disease.
DESIGN: Double-blind, randomized, controlled clinical trial.
SETTING: Pretests and posttests were conducted in an academic health science center.
PARTICIPANTS: Forty-three ambulatory subjects with chronic pain in 1
or both knee joints who were recruited from outpatient clinics or who
volunteered to participate.
INTERVENTION: Subjects wore pads containing magnets or placebos over their painful knee joints for 2 weeks.
MAIN OUTCOME MEASURES: Self-administered ratings of pain and physical
function using the Western Ontario and Mc Master Universities
Osteoarthritis Index (WOMAC) and a timed 15-m (50-ft) walk.
RESULTS: Multivariate analysis of covariance revealed significantly
greater improvements in the group wearing magnets (P=.002). Univariate
analyses indicated that comparative changes in self-rated pain and
physical function (P=.002 and .001, respectively) were greater than
changes in gait speed (P=.042).
CONCLUSIONS: The application of static magnets over painful knee joints appears to reduce pain and enhance functional movement. However, further study is needed to determine the physiological mechanisms responsible for this analgesic effect.
Alternative Therapies in Health and Medicine. 2002 Jul-Aug;8(4):50-5.
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Use of a permanent magnetic field to inhibit the development of canine osteoarthritis
Rogachefsky RA, Altman RD, Markov MS, Cheung HS.
Department of Orthopedics, University of Miami School of Medicine, Miami, Florida, USA.
This study was designed to determine the potential of a permanent
magnetic field to inhibit the progression of osteoarthritis (OA) in a
canine model.
The magnetic field was created by 72 domino-sized ceramic magnets
with surface field strength of 1100 G (0.11 T). The magnetic field
strength at the surface of the mattress was 450-500 G (45-50 mT) and was
equally distributed over the mattress surface.
Eighteen animals had closed resection of their right stifle anterior
cruciate ligament. Their kennel floors were covered in one of three
ways: no floor mattress (OA) (N = 6); a floor mattress with domino-sized
ceramic pieces placed between two layers of foam (sham control OA-MAT)
(N = 6); or a floor mattress with domino-sized ceramic permanent magnets
placed between two layers of foam (OA-MAT-MAG) (N = 6). Animals were
kept in their cages except for 4 h of exercise each day. The left stifle
of six animals served as the normal control. The stifle joints were
examined at 12 weeks for synovial effusion, gross anatomic appearance,
microscopic anatomic appearance (Mankin score), and metalloproteinase
(MMP)-1 and -3.
Macroscopically, the OA-MAT-MAG group appeared to have less
synovitis, less synovial effusion, less disruption of the cartilage
surface, and less cartilage ulceration than did the OA group or the
control mattress group. The mean Mankin score for the
OA-MAT-MAG group was less than that for the OA group (4.2 +/- 0.8 vs.
6.7 +/- 0.3; P <.05) and the control mattress group (4.2 +/- 0.8 vs.
5.2 +/- 0.8; P >.05), but greater than that for the normal left group
(4.2 +/- 0.8 vs. 1.0 +/- 0.4; P <.05). These scores show a trend of
improvement for OA-MAT-MAG group but the difference with the sham
control OA-MAT group was not statistically significant. In
immunohistochemical studies, the OA-MAT-MAG group cartilage was stained
less heavily for MMP-1 and MMP-3 than were the OA group cartilage and
the control mattress group cartilage, but did not differ significantly
in MMP-1 and MMP-3 from the normal left group cartilage. The OA-MAT-MAG
group did not differ from the normal left group in MMP-3 as determined
by Western blot analysis.
The study suggests that OA of the medial femoral condyle developed in
a canine model exposed to a magnetic field may be inhibited beyond the
benefit provided by mattress. Further studies are needed to delineate
more precisely the effect of the magnetic field in reducing the severity
of OA.
Rogachefsky RA, Altman RD, Markov MS, Cheung HS (May 2004). "Use of a
permanent magnetic field to inhibit the development of canine
osteoarthritis." Bioelectromagnetics. 25(4):260-70. PMID: 15114635
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Randomized controlled trial of magnetic bracelets for relieving pain in osteoarthritis of the hip and knee
Objective: To determine the effectiveness of commercially
available magnetic bracelets for pain control in osteoarthritis of the
hip and knee. Design: Randomized, placebo controlled trial with three parallel groups. Setting: Five rural general practices. Participants: 194 men and women aged 45-80 years with osteoarthritis of the hip or knee.
Intervention: Wearing a standard strength static bipolar
magnetic bracelet, a weak magnetic bracelet, or a non-magnetic (dummy)
bracelet for 12 weeks. Main outcome measures Change in the Western
Ontario and Mc Master Universities osteoarthritis lower limb pain scale
(WOMAC A) after 12 weeks, with the primary comparison between the
standard and dummy groups. Secondary outcomes included changes in WOMAC B
and C scales and a visual analogue scale for pain.
Results: Mean pain scores were reduced more in the standard
magnet group than in the dummy group (mean difference 1.3 points, 95%
confidence interval 0.05 to 2.55). Self reported blinding status did not
affect the results. The scores for secondary outcome measures were
consistent with the WOMAC A scores.
Conclusion: Pain from osteoarthritis of the hip and knee
decreases when wearing magnetic bracelets. It is uncertain whether this
response is due to specific or non-specific (placebo) effects.
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Comparison between the analgesic and therapeutic effects of a
musically modulated electromagnetic field (TAMMEF) and those of a 100 Hz
electromagnetic field: blind experiment on patients suffering from
cervical spondylosis or shoulder periarthritis.
Rigato M, Battisti E, Fortunato M, Giordano N.
Department of Physics, Section of Medical Physics University of Sienna, Italy. rigato@unisi.it
The analgesic-therapeutic efficacy and tolerability of a
low-frequency electromagnetic field (ELF), modulated at a frequency of
100 Hz with a sinusoidal waveform and mean induction of a few gauss, has
been demonstrated by the authors in numerous previous studies of
various hyperalgic pathologies, particularly of the locomotor apparatus.
In the present study, the authors tested a new type of all-inclusive
field, denoted TAMMEF, whose parameters (frequency, intensity, waveform)
are modified in time, randomly varying within the respective ranges, so
that all the possible codes can occur during a single application. For
the comparison, 150 subjects (118 women and 32 men, between 37 and 66
years of age) were enrolled. They were affected by cervical spondylosis
(101 cases) or shoulder periarthritis (49 cases). Unbeknownst to them,
they were randomly divided into three groups of 50 subjects. One group
was exposed to the new TAMMEF, another group to the usual ELF, and the
third group to simulated treatment. The results show that the effects of
the new TAMMEF therapy are equivalent to those obtained with the ELF.
Journal of Medical Engineering and Technology. 2002 Nov-Dec;26(6):253-8.
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The conservative treatment of osteonecrosis of the femoral head. A
comparison of core decompression and pulsing electromagnetic fields.
Aaron RK, Lennox D, Bunce GE, Ebert T.
University of Rhode Island, Kingston.
Once roentgenographic changes are apparent, osteonecrosis of the
femoral head in the adult generally progresses to osteoarthritis within
two to three years. A variety of conservative surgical procedures have
been devised to conserve the femoral head with varying success. This
study examines the effectiveness of pulsing electromagnetic fields and
core decompression in the treatment of osteonecrosis of the femoral
head. Both techniques reduce the incidence of clinical and
roentgenographic progression. Exposure to pulsing electromagnetic fields
appears to be more effective in hips with Ficat II lesions than in hips
with more advanced lesions.
Clinical Orthopaedics. 1989 Dec;(249):209-18.
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A double-blind trial of the clinical effects of pulsed electromagnetic fields in osteoarthritis.
Trock DH, Bollet AJ, Dyer RH Jr, Fielding LP, Miner WK, Markoll R.
Department of Medicine (Rheumatology), Danbury Hospital, CT 06810.
OBJECTIVE: Further evaluation of pulsed electromagnetic fields
(PEMF), which have been observed to produce numerous biological effects,
and have been used to treat delayed union fractures for over a decade.
METHODS: In a pilot, double-blind randomized trial, 27 patients with
osteoarthritis (OA), primarily of the knee, were treated with PEMF.
Treatment consisted of 18 half-hour periods of exposure over about 1
month in a specially designed non contact, air-coil device. Observations
were made on 6 clinical variables at baseline, midpoint of therapy, end
of treatment and one month later; 25 patients completed treatment.
RESULTS: An average improvement of 23-61% occurred in the clinical
variables observed with active treatment, while 2 to 18% improvement was
observed in these variables in placebo treated control patients. No
toxicity was observed.
CONCLUSION: The decreased pain and improved functional performance of
treated patients suggests that this configuration of PEMF has potential
as an effective method of improving symptoms in patients with OA. This
method warrants further clinical investigation.
Journal of Rheumatology. 1993 Mar;20(3):456-60.
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Treatment of experimental inflammatory synovitis with continuous magnetic field.
Weinberger A, Nyska A, Giler S.
Department of Medicine, Rabin Medical Center, Petah Tikva, Israel.
The effect of a magnetic field on synovitis in rats was studied.
Synovitis was induced by bilateral intraarticular injection of zymosan
to the hind joints. One group of rats was held in a cage with a magnet
of 3,800 Gauss on the bottom of the cage (treated), while another group
was held in a cage without a magnet (control). Three weeks following
intraarticular zymosan injection all rats were killed and the hind
joints tissues were examined histologically. The pathologic process was
noted and graded according to the involvement of various tissue
components, number of inflammatory foci, and size of the lesion. The
histologic findings of the tissues from the control group consisted of
marked articular infiltrate, composed of lymphocytes and plasma cells
with some histocytes in 80% of the animals. A small articular
infiltration of the same nature was observed in 20% of the treated rats.
The inflammatory score was 3.4 +/- 1.1 in the treated animals and 6.8
+/- 2.6 in the control group (P = 0.002). These data showed that synovitis and the inflammatory process are significantly suppressed by a magnetic field.
Israeli Journal of Medical Sciences. 1996 Dec;32(12):1197-201.
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Effects of electromagnetic fields in experimental fracture repair.
Otter MW, McLeod KJ, Rubin CT.
Program in Biomedical Engineering, State University of New York at Stony Brook 11794-8181, USA.
The clinical benefits of electromagnetic fields have been claimed for
20 centuries, yet it still is not clear how they work or in what
circumstances they should be used. There is a large body of evidence
that steady direct current and time varying electric fields are
generated in living bone by metabolic activity and mechanical
deformation, respectively. Externally supplied direct currents have been
used to treat nonunion's, appearing to trigger mitosis and recruitment
of osteogenic cells, possibly via electrochemical reactions at the
electrode-tissue interface. Time varying electromagnetic fields also
have been used to heal nonunion's and to stabilize hip implants, fuse
spines, and treat osteonecrosis and osteoarthritis. Recent research into
the mechanism(s) of action of these time varying fields has
concentrated on small, extremely low frequency sinusoidal electric
fields. The osteogenic capacity of these fields does not appear to
involve changes in the transmembrane electric potential, but instead
requires coupling to the cell interior via transmembrane receptors or by
mechanical coupling to the membrane itself.
Clinical Orthopaedics. 1998 Oct;(355 Suppl):S90-104.
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Electrical stimulation of human femoral intertrochanteric osteotomies. Double-blind study.
Borsalino G, Bagnacani M, Bettati E, Fornaciari F, Rocchi R, Uluhogian S, Ceccherelli G, Cadossi R, Traina GC.
Department of Orthopaedics and Traumatology, Montecchio Hospital, Reggio Emilia, Italy.
Low-frequency pulsing electromagnetic fields (PEMF) are being used in
nonunion healing at several centers around the world. Much debate
exists about quantification of PEMF effects, especially in humans where
no randomized studies have been performed. The results of a double-blind
treatment of 32 consecutive patients treated with femoral
intertrochanteric osteotomy for hip degenerative arthritis are reported.
Roentgenographic evaluation and callus density measurements performed
with an image analyzer showed a statistically significant difference
between controls and stimulated patients (p less than 0.01). In this
extremely homogeneous patient population, PEMF stimulation favored
osteotomy healing.
Clinical Orthopaedics. 1988 Dec;(237):256-63.
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Electrical stimulation of osteonecrosis of the femoral head.
Aaron RK, Steinberg ME.
Department of Orthopaedics, Brown University, Providence, RI.
Osteonecrosis of the femoral head in the adult is a progressive
condition that, if untreated, usually results in femoral head collapse
and secondary osteoarthritis. The experimental application of electrical
and electromagnetic fields has been shown to favorably affect a number
of biological processes pertinent to osteonecrosis of the femoral head
and has led to several clinical trials. The condition has been treated
by the application of electrical fields invasively by the surgical
implantation of electrodes within the femoral head and noninvasively by
capacitative or inductive coupling. This review describes results in
osteonecrosis of the femoral head with these therapeutic techniques. Stimulation by means of inductive coupling with pulsed magnetic fields seems to be the most promising technique studied so far, but the optimal signal characteristics and device design are not yet known.
Seminars in Arthroplasty. 1991 Jul;2(3):214-21.
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The electrical stimulation of tibial osteotomies. Double-blind study.
Mammi GI, Rocchi R, Cadossi R, Massari L, Traina GC.
Department of Orthopaedics and Traumatology, Ospedale Civile C. Magati, Scandiano (RE), Italy.
The effect of electromagnetic field stimulation was investigated in a
group of 40 consecutive patients treated valgus tibial osteotomy for
degenerative arthrosis of the knee. All patients were operated on by the
same author and followed the same postoperative program. After surgery,
patients were randomly assigned to a control group (dummy stimulators)
or to a stimulated one (active stimulators). Four orthopedic surgeons,
unaware of the experimental conditions, were asked to evaluate the
roentgenograms taken 60 days postoperatively and to rate the osteotomy
healing according to four categories (the fourth category being the most
advanced stage of healing). In the control group, 73.6% of the patients
were included in the first and second category. In the stimulated
group, 72.2% of the patients were included in the third and fourth
category. On a homogeneous group of patients, electromagnetic field stimulation had positive effects on the healing of tibial osteotomies.
Clinical Orthopaedics. 1993 Mar;(288):246-53.
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Electromagnetic fields for the treatment of osteoarthritis.
Hulme J, Robinson V, DeBie R, Wells G, Judd M, Tugwell P.
Cochrane Collaborating Center, Center for Global Health, Institute of
Population Health - University of Ottawa, 1 Stewart Street, Ottawa,
Ontario, Canada, K1N 6N5. jhulme@uottawa.ca
BACKGROUND: As the focus for osteoarthritis (OA) treatment shifts
away from drug therapy, we consider the effectiveness of pulsed electric
stimulation which is proven to stimulate cartilage growth on the
cellular level.
OBJECTIVES: 1)To assess the effectiveness of pulsed electric
stimulation for the treatment of osteoarthritis (OA). 2) To assess the
most effective and efficient method of applying an electromagnetic
field, through pulsed electromagnetic fields (PEMF) or electric
stimulation, as well as the consideration of length of treatment,
dosage, and the frequency of the applications.
SEARCH STRATEGY: We searched PREMEDLINE, MEDLINE, HealthSTAR, CINAHL,
PEDro, and the Cochrane Controlled Trials Register (CCTR) up to and
including 2001. This included searches through the coordinating offices
of the trials registries of the Cochrane Field of Physical and Related
Therapies and the Cochrane Musculoskeletal Group for further published
and unpublished articles. The electronic search was complemented by hand
searches and experts in the area.
SELECTION CRITERIA: Randomized controlled trials and controlled
clinical trials that compared PEMF or direct electric stimulation
against placebo in patients with OA.
DATA COLLECTION AND ANALYSIS: Two reviewers determined the studies to
be included in the review based on inclusion and exclusion criteria
(JH,VR) and extracted the data using pre-developed extraction forms for
the Cochrane Musculoskeletal Group. The methodological quality of the
trials was assessed by the same reviewers using a validated scale (Jadad
1996). Osteoarthritis outcome measures were extracted from the
publications according to OMERACT guidelines (Bellamy 1997) and
additional secondary outcomes considered.
MAIN RESULTS: Only three studies with a total of 259 OA patients were
included in the review. Electrical stimulation therapy had a small to
moderate effect on outcomes for knee OA, all statistically significant
with clinical benefit ranging from 13-23% greater with active treatment
than with placebo. Only 2 outcomes for cervical OA were significantly
different with PEMF treatment and no clinical benefit can be reported
with changes of 12% or less.
REVIEWER'S CONCLUSIONS: Current evidence suggests that electrical
stimulation therapy may provide significant improvements for knee OA,
but further studies are required to confirm whether the statistically
significant results shown in these trials confer to important benefits.
Cochrane Database Systematic Review. 2002;(1):CD003523.
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Low-amplitude, extremely low frequency magnetic fields for the treatment of osteoarthritic knees: a double-blind clinical study.
Jacobson JI, Gorman R, Yamanashi WS, Saxena BB, Clayton L.
Institute of Theoretical Physics and Advanced Studies for Biophysical Research, Perspectivism Foundation
CONTEXT: Noninvasive magnetotherapeutic approaches to bone healing have been successful in past clinical studies.
OBJECTIVE: To determine the effectiveness of low-amplitude, extremely
low frequency magnetic fields on patients with knee pain due to
osteoarthritis.
DESIGN: Placebo-controlled, randomized, double-blind clinical study.
SETTING: 4 outpatient clinics.
PARTICIPANTS: 176 patients were randomly assigned to 1 of 2 groups,
the placebo group (magnet off) or the active group (magnet on).
INTERVENTION: 6-minute exposure to each magnetic field signal using 8
exposure sessions for each treatment session, the number of treatment
sessions totaling 8 during a 2-week period, yielded patients being
exposed to uniform magnetic fields for 48 minutes per treatment session 8
times in 2 weeks. The magnetic fields used in this study were generated
by a Jacobson Resonator, which consists of two 18-inch diameter (46-cm
diameter) coils connected in series, in turn connected to a function
generator via an attenuator to obtain the specific amplitude and
frequency. The range of magnetic field amplitudes used was from 2.74 x
10(-7) to 3.4 x 10(-8) G, with corresponding frequencies of 7.7 to 0.976
Hz.
OUTCOME MEASURES: Each subject rated his or her pain level from 1
(minimal) to 10 (maximal) before and after each treatment and 2 weeks
after treatment. Subjects also recorded their pain intensity in a diary
while outside the treatment environment for 2 weeks after the last
treatment session (session 8) twice daily: upon awakening (within 15
minutes) and upon retiring (just before going to bed at night).
RESULTS: Reduction in pain after a treatment session was
significantly (P < .001) greater in the magnet-on group (46%)
compared to the magnet-off group (8%).
CONCLUSION: Low-amplitude, extremely low frequency magnetic
fields are safe and effective for treating patients with chronic knee
pain due to osteoarthritis.
Alternative Therapies in Health and Medicine. 2001 Sep-Oct;7(5):54-64, 66-9
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Magnetic pulse treatment for knee osteoarthritis: a randomized, double-blind, placebo-controlled study.
Pipitone N, Scott DL.
Rheumatology Department, King's College Hospital (Dulwich), London, UK.
We assessed the efficacy and tolerability of low-frequency pulsed
electromagnetic fields (PEMF) therapy in patients with clinically
symptomatic knee osteoarthritis (OA) in a randomised,
placebo-controlled, double-blind study of six weeks' duration. Patients
with radiographic evidence and symptoms of OA (incompletely relieved by
conventional treatments), according to the criteria of the American
College of Rheumatology, were recruited from a single tertiary referral
centre. 75 patients fulfilling the above criteria were randomised to
receive active PEMF treatment by unipolar magnetic devices (Medicur)
manufactured by Snowden Healthcare (Nottingham, UK) or placebo. Six
patients failed to attend after the screening and were excluded from
analysis. The primary outcome measure was reduction in overall pain
assessed on a four-point Likert scale ranging from nil to severe.
Secondary outcome measures included the WOMAC Osteoarthritis Index
(Likert scale) and the EuroQol (Euro-Quality of Life, EQ-5D). Baseline
assessments showed that the treatment groups were equally matched.
Although there were no significant differences between active and sham
treatment groups in respect of any outcome measure after treatment,
paired analysis of the follow-up observations on each patient showed
significant improvements in the actively treated group in the WOMAC
global score (p = 0.018), WOMAC pain score (p = 0.065), WOMAC disability
score (p = 0.019) and EuroQol score (p = 0.001) at study end compared
to baseline. In contrast, there were no improvements in any variable in
the placebo-treated group. There were no clinically relevant adverse
effects attributable to active treatment. These results suggest that the
Medicur unipolar magnetic devices are beneficial in reducing pain and
disability in patients with knee OA resistant to conventional treatment
in the absence of significant side-effects. Further studies using
different types of magnetic devices, treatment protocols and patient
populations are warranted to confirm the general efficacy of PEMF
therapy in OA and other conditions.
Current Medical Research and Opinion. 2001;17(3):190-6.
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Modification of osteoarthritis by pulsed electromagnetic field--a morphological study.
Ciombor DM, Aaron RK, Wang S, Simon B.
Department of Orthopaedics, Brown Medical School, Providence, RI 02906, USA.
OBJECTIVE: Hartley guinea pigs spontaneously develop arthritis that
bears morphological, biochemical, and immunohistochemical similarities
to human osteoarthritis. It is characterized by the appearance of
superficial fibrillation by 12 months of age and severe cartilage
lesions and eburnation by 18 months of age. This study examines the
effect of treatment with a pulsed electromagnetic field (PEMF) upon the
morphological progression of osteoarthritis in this animal model.
DESIGN: Hartley guinea pigs were exposed to a specific PEMF for
1h/day for 6 months, beginning at 12 months of age. Control animals were
treated identically, but without PEMF exposure. Tibial articular
cartilage was examined with histological/histochemical grading of the
severity of arthritis, by immunohistochemistry for cartilage
neoepitopes, 3B3(-) and BC-13, reflecting enzymatic cleavage of
aggrecan, and by immunoreactivity to collagenase (MMP-13) and
stromelysin (MMP-3). Immunoreactivity to TGFbeta, interleukin
(IL)-1beta, and IL receptor antagonist protein (IRAP) antibodies was
examined to suggest possible mechanisms of PEMF activity.
RESULTS: PEMF treatment preserves the morphology of articular
cartilage and retards the development of osteoarthritic lesions. This
observation is supported by a reduction in the cartilage neoepitopes,
3B3(-) and BC-13, and suppression of the matrix-degrading enzymes,
collagenase and stromelysin. Cells immunopositive to IL-1 are decreased
in number, while IRAP-positive cells are increased in response to
treatment. PEMF treatment markedly increases the number of cells
immunopositive to TGFbeta.
CONCLUSIONS: Treatment with PEMF appears to be disease-modifying in this model of osteoarthritis.
Since TGFbeta is believed to upregulate gene expression for aggrecan,
downregulate matrix metalloprotease and IL-1 activity, and upregulate
inhibitors of matrix metalloprotease, the stimulation of TGFbeta may be a
mechanism through which PEMF favorably affects cartilage homeostasis.
Osteoarthritis Cartilage. 2003 Jun;11(6):455-62.
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Pulsed magnetic field therapy for osteoarthritis of the knee--a double-blind sham-controlled trial.
Nicolakis P, Kollmitzer J, Crevenna R, Bittner C, Erdogmus CB, Nicolakis J.
Department of Physical Medicine and Rehabilitation, AKH Wien,
University of Vienna, Vienna, Austria. Peter.nicolakis@akh-wien.ac.at
BACKGROUND AND METHODS: Pulsed magnetic field therapy is frequently
used to treat the symptoms of osteoarthritis, although its efficacy has
not been proven. We conducted a randomized, double-blind comparison of
pulsed magnetic field and sham therapy in patients with symptomatic
osteoarthritis of the knee. Patients were assigned to receive 84
sessions, each with a duration of 30 minutes, of either pulsed magnetic
field or sham treatment. Patients administered the treatment on their
own at home, twice a day for six weeks.
RESULTS: According to a sample size estimation, 36 consecutive
patients were enrolled. 34 patients completed the study, two of whom had
to be excluded from the statistical analysis, as they had not applied
the PMF sufficiently. Thus, 15 verum and 17 sham-treated patients were
enrolled in the statistical analysis. After six weeks of treatment the
WOMAC Osteoarthritis Index was reduced in the pulsed magnetic
field-group from 84.1 (+/- 45.1) to 49.7 (+/- 31.6), and from 73.7 (+/-
43.3) to 66.9 (+/- 52.9) in the sham-treated group (p = 0.03). The
following secondary parameters improved in the pulsed magnetic field
group more than they did in the sham group: gait speed at fast walking
[+6.0 meters per minute (1.6 to 10.4) vs. -3.2 (-8.5 to 2.2)], stride
length at fast walking [+6.9 cm (0.2 to 13.7) vs. -2.9 (-8.8 to 2.9)],
and acceleration time in the isokinetic dynamometry strength tests
[-7.0% (-15.2 to 1.3) vs. 10.1% (-0.3 to 20.6)].
CONCLUSION: In patients with symptomatic osteoarthritis of the
knee, PMF treatment can reduce impairment in activities of daily life
and improve knee function.
Wiener Klinische Wochenschrift. 2002 Aug 30;114(15-16):678-84
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Personal experience in the use of magnetotherapy in diseases of the musculoskeletal system.
Sadlonova J, Korpas J.
1st Dept of Internal Medicine, Jessenius Faculty of Medicine, Comenius University, Martin, Slovakia.
Therapeutic application of pulsatile electromagnetic field in
disorders of motility is recently becoming more frequent. Despite this
fact information about the effectiveness of this therapy in the
literature are rare. The aim of this study was therefore the treatment
of 576 patients who suffered from vertebral syndrome, gonarthritis and
coxarthritis. For application of pulsatile electromagnetic field MTU
500H Therapy System was used. Pulsatile electromagnetic field had a
frequency value of 4.5 mT in all studied groups and magnetic induction
value 12.5-18.75 mT in the 1st group. In the 2nd group the intensity was
5.8-7.3 mT and in the 3rd group it was 7.6-11.4 mT. The time of
inclination/declination in the 1st group was 20/60 ms, in the 2nd group
40/80 ms and in the 3rd group 40/90 ms. The electromagnetic field was
applied during 10 days. In the 1st-3rd day during 20 minutes and in the
4th-10th day during 30 minutes. The therapy was repeated in every
patient after 3 months with values of intensity higher by 50%. In the
time of pulsatile electro-magnetotherapy the patients were without
pharmacotherapy or other physiotherapy. The application of pulsatile
electromagnetic field is a very effective therapy of vertebral syndrome,
gonarthritis and coxarthritis. The results have shown that the therapy
was more effective in patients suffering from gonarthrosis, than in
patients with vertebral syndrome and least effective in patients with
coxarthosis. Owing to regression of oedema and pain relief the motility
of patients improved. (Tab. 3, Ref. 19.)
Bratisl Lek Listy. 1999 Dec;100(12):678-81.
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