Low-amplitude, extremely low frequency magnetic fields for the treatment of osteoarthritic knees: a double-blind clinical study.
BACKGROUND
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.


METHODS
Placebo-controlled, randomized, double-blind clinical study.


METHODS
4 outpatient clinics.


METHODS
176 patients were randomly assigned to 1 of 2 groups, the placebo group (magnet off) or the active group (magnet on).


METHODS
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.


METHODS
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%).


CONCLUSIONS
Low-amplitude, extremely low frequency magnetic fields are safe and effective for treating patients with chronic knee pain due to osteoarthritis.
Jacobson
J I
JI
Institute of Theoretical Physics and Advanced Studies for Biophysical Research, Perspectivism Foundation, 2006 Mainsail Cir, Jupiter, FL 33477-1418, USA. drjjacobson@aol.com
Gorman
R
R
Yamanashi
W S
WS
Saxena
B B
BB
Clayton
L
L
D000328:Adult; D004311:Double-Blind Method; D004574:Electromagnetic Fields; D005260:Female; D006801:Humans; D008280:Magnetics / Q000627:therapeutic use*; D008297:Male; D020370:Osteoarthritis, Knee / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D010146:Pain / Q000209:etiology / Q000503:physiopathology; D059408:Pain Management; D010147:Pain Measurement / Q000379:methods / Q000706:statistics & numerical data