Modulation of bone loss during disuse by pulsed electromagnetic fields

Abstract

The effect of pulsed electromagnetic fields (PEMFs) on bone loss associated with disuse was investigated by applying 1.5 Hz repetitions of 30 ms bursts of asymmetric pulses, varying from +2.5 to -135 mV, to bones deprived of their normal functional loading. The proximal portion of one fibula in each of a group of ovariectomised adult female beagle dogs was isolated from functional loading in vivo by proximal and distal osteotomies. Comparison of these prepared bones with their intact contralateral controls after 12 weeks, showed a 23% reduction in cross-sectional area. In similarly prepared bones exposed to PEMFs for 1 h per day, 5 days per week, this bone loss was substantially and significantly reduced to 9% (p = 0.029). There was no evidence of any new bone formation on the periosteal surface of prepared fibulae in treated or untreated situations. PEMF treatment was not associated with any significant change in number of osteons per mm2 formed within the cortex of the bones, their radial closure rate, or their degree of closure. The modulation in loss of bone area associated with exposure to PEMFs can, therefore, be inferred to be due to a reduction in resorption on the bone surface.

The preventive effects of pulsed electromagnetic fields on diabetic bone loss in streptozotocin-treated rats

“…Several experimental studies have demonstrated that PEMF stimulation could prevent bone mass loss and microarchitecture deterioration, and improve bone's biomechanical properties in various animal models of osteoporosis [16][17][18]. This efficiency of PEMF was further confirmed by numerous clinical investigations [19,20].…”

Pulsed electromagnetic fields prevent osteoporosis in an ovariectomized female rat model: A prostaglandin E2‐associated process

“…Mishima [1988] found pulse burst waves at a positive amplitude of 25 mV, burst width of 4.2 ms, pulse width of 230 ms, and repetition rate of 12 Hz to be effective in preventing osteoporosis caused by bilateral ovariectomy and right sciatic neurectomy in rats. Skerry et al [1991] found that pulse burst with burst width of 30 ms, repetition rate of 1.5 Hz, and positive amplitude of 2.5 mV had the capability to inhibit the bone loss in disuse osteoporosis. Rubin et al [1989] used a turkey model of disuse osteoporosis to show that pulse burst with 30 ms bursts at a repetition rate of 1.5 Hz and each burst containing 120 repetitions of an asymmetrical pulse were effective in preventing bone loss by regulating cortical bone remodeling.…”

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

“…Given this background it would be natural to ask whether PEMFs could have a benefit in preserving bone mass in situations that lead to osteopenia, such as disuse. There have been a number of experiments in animal models of osteopenia that support such a beneficial effect after mechanical unloading [Bassett et al, 1979;Cruess and Bassett, 1983;Rubin et al, 1989;Skerry et al, 1991;Shen and Zhao, 2010] or ovariectomy [Zati et al, 1993;Bilotta et al, 1994;Chang and Chang, 2003]. On the other hand, we found only a few reports of the attempt to improve bone density in humans using low frequency or PEMFs in osteoporosis [Tabrah et al, 1990[Tabrah et al, , 1998Bilotta et al, 1994;Giordano et al, 2001], or in other situations [Eyres et al, 1996;Garland et al, 1999] but they were generally small and/or not well controlled.…”