of the knee
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,
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
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.
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 MEASURES:
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
Randomized Controlled Trial
PMID: 15055092 [PubMed - indexed for MEDLINE]