title: Electromagnetic fields: a novel prophylaxis for steroid-induced osteonecrosis.
abstract: Establishing a means to prevent osteonecrosis after corticosteroid administration is an important theme. We asked whether pulsed electromagnetic field stimulation, a noninvasive treatment, could prevent osteonecrosis. Ninety rabbits were divided into four treatment groups: (1) exposure of 10 hours per day to electromagnetic stimulation for 1 week, followed by injection of methylprednisolone (20 mg/kg), and exposure of 10 hours per day to electromagnetism for a further 4 weeks (n = 40); (2) methylprednisolone injection only (n = 40); (3) no treatment (n = 5); and (4) exposure of 10 hours per day to electromagnetism for 5 weeks (n = 5). After 5 weeks, we harvested and histologically examined femurs bilaterally. The frequency of osteonecrosis was lower in the steroid-electromagnetism group (15/40) than in the steroid-only group (26/40). No necrotic lesions were found in the two control groups. We observed no clear effects of electromagnetism on the number, location, extent, and repair of necrotic lesions and intramedullary fat cell size in affected rabbits. Pulsed electromagnetic field stimulation reportedly augments angiogenesis factors and dilates blood vessels; these effects may lower the frequency of osteonecrosis. Exposure to pulsed electromagnetic field stimulation before corticosteroid administration could be an effective means to reduce the risk of osteonecrosis.
authors: Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
authors: Masashi
authors: M
authors: Ishida
authors: Mikihiro
authors: M
authors: Fujioka
authors: Kenji A
authors: KA
authors: Takahashi
authors: Yuji
authors: Y
authors: Arai
authors: Toshikazu
authors: T
authors: Kubo
mesh_terms: D017667:Adipocytes / Q000528:radiation effects; D000818:Animals; D001854:Bone Marrow Cells / Q000528:radiation effects; D048429:Cell Size; D004195:Disease Models, Animal; D004599:Electric Stimulation Therapy / Q000295:instrumentation / Q000379:methods*; D004574:Electromagnetic Fields; D004867:Equipment Design; D005269:Femur / Q000473:pathology / Q000528:radiation effects*; D005271:Femur Head Necrosis / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D008297:Male; D008775:Methylprednisolone; D011817:Rabbits; D013997:Time Factors
chemical_list: D008775:Methylprednisolone