Electromagnetic effects on forearm disuse osteopenia: A randomized, double-blind, sham-controlled study

Abstract

A randomized, double-blind, sham-controlled, feasibility and dosing study was undertaken to determine if a common pulsing electromagnetic field (PEMF) treatment could moderate the substantial osteopenia that occurs after forearm disuse. Ninety-nine subjects were randomized into four groups after a distal radius fracture, or carpal surgery requiring immobilization in a cast. Active or identical sham PEMF transducers were worn on the distal forearm for 1, 2, or 4 h/day for 8 weeks starting after cast removal ("baseline") when bone density continues to decline. Bone mineral density (BMD) and bone geometry were measured in the distal forearm by dual energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) at entry ("baseline") and 8, 16, and 24 weeks later. Significant average BMD losses after baseline were observed in the affected forearm at all time points (5-7% distally and 3-4% for the radius/ulna shaft). However, after adjusting for age, gender, and baseline BMD there was no evidence of a positive effect of active versus sham PEMF treatment on bone loss by DXA or pQCT for subjects completing all visits (n = 82, ∼20 per group) and for an intent-to-treat analysis (n = 99). Regardless of PEMF exposure, serum bone-specific alkaline phosphatase (BSAP) was normal at baseline and 8 weeks, while serum c-terminal collagen teleopeptide (CTX-1) was markedly elevated at baseline and less so at 8 weeks. Although there was substantial variability in disuse osteopenia, these results suggested that the particular PEMF waveform and durations applied did not affect the continuing substantial disuse bone loss in these subjects.

Effects of pulsed electromagnetic fields on postmenopausal osteoporosis

“…In contrast to the above‐mentioned studies, no significant increase in BMD after 3 months could be found in a single‐blind and randomized pilot study [Giordano et al, ], which adopted the following parameters: 100 Hz and 10 ± 2 G PEMF exposure. Similarly, another randomized and sham‐controlled study [Spadaro et al, ] found that the parameters of 8 weeks, 15 Hz, and 2 mT PEMFs did not result in long‐term positive changes in BMD in subjects with forearm disuse osteopenia, after adjusting for age, gender, and baseline BMD.…”

“…Though negative BMD change was reported in a trial [Giordano et al, ], the authors found that PEMF exposure with parameters of 100 Hz and 2.85 mT (60 min/day, 3 times a week for 3 months) could increase serum osteocalcin (OC) and PINP levels, which were biomarkers associated with bone formation. Similarly, PEMFs with parameters of 8 weeks, 15 Hz, and 2 mT maintained the expected normal level of serum bone‐specific alkaline phosphatase (BSAP) and decreased CTX level, which were independent of BMD change, but were still beyond normal levels in patients with forearm disuse osteopenia [Spadaro et al, ].…”

Pulsed electromagnetic fields on postmenopausal osteoporosis in southwest China: A randomized, active‐controlled clinical trial

“…Since no previous study was ever conducted regarding the effect of PEMFs on PMO, especially with these very parameters, it seems theoretically impractical to calculate the sample size. Instead, we estimated it to be 20 per group, similar to that of the study exploring the treatment effect of PEMFs on forearm disuse osteopenia [Spadaro et al, 2011]. To test the rationality of this estimation, we calculated the statistical power for the primary endpoint, the mean percentage change in bone mineral density of the lumbar spine (BMDL), from baseline at the last visit.…”

“…Since then, much evidence has positively supported the treatment effect of PEMFs for osteoporosis, although with an effective window [Rubin et al, 1989; Tabrah et al, 1990; Eyres et al, 1996; Garland et al, 1999; Giordano et al, 2001]. In addition, various biochemical mechanisms have been associated with its effectiveness [Shankar et al, 1998; Chang and Chang, 2003; Sun et al, 2009; Chen et al, 2010; Shen and Zhao, 2010] and there seems to be no detrimental side effects [Blaszczak et al, 2009] or sufficient amplitude to elicit neuromuscular responses [Radon et al, 2001; Spadaro et al, 2011]. But, negative results were also reported.…”

“…But, negative results were also reported. For example, no significant effect was observed on forearm disuse osteopenia [Spadaro et al, 2011], which was assumed to be attributed to the treatment starting point, duration, daily exposure time, PEMF waveform, and participant‐related factors.…”