Comparative study of bone growth by pulsed electromagnetic fields

Abstract

Pulsed electromagnetic fields have been widely used for treatment of non-united fractures and congenital pseudarthrosis. Several electrical stimulation systems such as air-cored and iron-cored coils and solenoids have been used the world over and claimed to be effective. Electrical parameters such as pulse shape, magnitude and frequency differ widely, and the exact bone-healing mechanism is still not clearly understood. The study attempts to analytically investigate the effectiveness of various parameters and suggests an optimal stimulation waveform. Mathematical analysis of electric fields inside the bone together with Fourier analysis of induced voltage waveforms produced by commonly used electrical stimulation wave-forms has been performed. A hypothesis based on assigning different weightings to different frequencies for osteogenic response has been proposed. Using this hypothesis astonishingly similar effective values of electric fields have been found in different systems. It is shown that effective electric field rather than peak electric field is the main parameter responsible for osteogenesis. The results are in agreement with experimental findings made on human beings by different investigators.

Effect of Pulsed Electromagnetic Fields on Human Mesenchymal Stem Cells Using 3D Magnetic Scaffolds

“…The samples were placed in the center of the coils where each coil consisted of 124 turns, outer coil diameter was 311 mm, inner coil diameter was 287 mm, mean coil radius was 150 mm, and coil resistance was 1.2 Ω. The magnitude of magnetic flux density (B) is calculated according to the following formula [Gupta et al, 1991]: where n is the number of turns in each coil, I is the current, R is the mean coil radius, and μ 0 is the permeability of free space (4 π × 10 −7 T·m/A), which leads to B = 7.433 × 10 −4 I in T .…”

“…The samples were placed in the center of the coils where each coil consisted of 124 turns, outer coil diameter was 311 mm, inner coil diameter was 287 mm, mean coil radius was 150 mm, and coil resistance was 1.2 Ω. The magnitude of magnetic flux density (B) is calculated according to the following formula [Gupta et al, 1991]:…”

Organ culture studies on the development of mouse embryo limb buds under EMF influence

“…Histograms of proliferation and differentiation changes in hindlimb buds at day 13.5 of development (means + SEM) (n ¼ 70 at each group), (a) number of mesenchymal cells, (b) number of degenerated cells (*p 5 0.05, **p 5 0.01, ***p 5 0.001). Bodamyali et al 1998, Cameron & Hunter 1985, Delgado et al 1982, Eyres et al 1996, Gupta et al 1991, Hand & Cadossi 1993, Levin 2003, Mclean et al 2001, Inoue et al 2002, Richards et al 1988, Xu et al 2000, Tenforde & Kaune 1987. The differences in results are due to a variety of factors including frequency, intensity, wave shape, effective time of EMF exposure and the kind of animals used.…”

Fracture healing in India: Available therapies, indications, and protocols

“…The absence of an identifiable source of funding makes it difficult to hold one sector of the government accountable. The NHP has set a goal to spend 8.5% of the GDP expenditure on the health system by 2011 10. Despite this, the public health system remains underfunded, and since it provides health care for over a quarter of the Indian population living below the poverty line, the NHP has not provided sufficient funding to provide care to the entire Indian population 3…”