Clinical Reviews-With Comments from Lynn Keegan, RN, PhD, HNC, FAAN
Magnet Therapy for the Treatment of Chronic Low Back Pain
Source: Collacott EA, et al. Bipolar permanent magnets for the treatment of chronic low back pain: A pilot study. JAMA 2000;283:1322-1325.
Context: Low back pain is one of the most frequent and expensive medical conditions in the United States. It is estimated that 85% of people will complain of low back pain during their lifetime, and currently more than 5 million people are disabled with this condition.
Objective: To compare the effectiveness of one type of therapeutic magnet, a bipolar permanent magnet, with a matching placebo device for patients with chronic low back pain.
Subjects: Nineteen men and one woman with stable low back pain, a mean of 19 years duration, and no past use of magnet therapy for the condition.
Design and Setting: Randomized, double-blind, placebo-controlled, crossover pilot study conducted from February 1998 to May 1999 in a Veterans Affairs Hospital ambulatory care physical medicine and rehabilitation clinic.
Interventions: For each patient, real and sham bipolar permanent magnets (300 gauss) were applied on alternate weeks for six hours per day, three days per week for one week with a one-week washout period between the two treatment weeks. The magnets were held into place with an abdominal binder, connected via velcro straps.
Main Outcome Measures: Pretreatment and post-treatment pain intensity on a visual analog scale (VAS); sensory and affective components of pain on the Pain Rating Index (PRI) of the McGill Pain Questionnaire; and range of motion measurements (ROM) of the lumbo-sacral spine, compared by real vs. sham treatment.
Results: Mean VAS scores declined by 0.49 (SD, 0.96) points for real magnet treatment and by 0.44 (SD, 1.4) points for sham treatment (P = 0.90). No statistically significant differences were noted in the effect between real and sham magnets with any of the other outcome measures (ROM, P = 0.66; PRI, P = 0.55).
Conclusion: Application of one variety of permanent magnet had no effect on this small group of subjects with chronic low back pain.
Comment: The public demand for magnetic devices to treat painful conditions is booming—people in North America spent about $200 million last year and international sales exceeded $5 billion. Magnets have been used to relieve pain since antiquity in locales from Greece to China, but only recently have scientists begun to test how well they really work. In this pilot study with a sample of 20, magnets had no effect on chronic low back pain. What we need to remember is that this was a small study, and that other studies with different populations and conditions are showing different results. It’s probably too soon to make any generalizations regarding the overall effectiveness of magnet therapy