 Joseph A Spadaro, Ph.D.Professor, Orthopedic Surgery 3119 Institute For Human Performance Research Program and Department AffiliationsBiomedical Sciences Program Research InterestsElectromagnetic and mechanical regulation of bone physiology, skeletal growth and bone density. Mechanical and Electrical Regulation of Bone Formation. With S. Albanese, W. Bergstrom This work aims at understanding and augmenting the physical regulatory mechanisms involved in adaptation, remodeling, and repair in the skeleton. In vivo models include epiphyseal growth, repair of bone defects, bone density, and calcium transport. Mechanical effects (e.g., implant motion, dynamic loading, vibration or ultrasonic energy) are thought to be mediated by cytoskeleton, membrane receptors or inflammatory mechanisms. Effects of electromagnetically induced currents seem to involve the regulatory pathways by which agents such as PTH or IGFs operate. Recent experiments show 30-50% changes in calcium uptake in calvarial bone disc bioassay (Bergstrom) from rats exposed to a weak, pulsed magnetic field (PEMF) for a few minutes. The electromagnetic stimulus seems to interfere with PTH activity and shows some frequency and waveform specificity. A PEMF applied to rabbits has also been shown to increase bone formation around a mechanically stimulated implant. Disuse Osteopenia in the Human Forearm as a Model for Osteoporosis. With W. Short, K. Mann Both intact and fractured bones tend to lose substance when loading is reduced in a cast or brace. 10-20% reduction in bone density may occur after 1-2 months. This phenomenon is being studied further in the forearm of patients after carpal surgery or distal radius fracture to determine the geometrical and temporal patterns of bone loss. Bone densitometry (DEXA), computed tomography (QCT) and structural analysis are the chief tools used, but biochemical markers of bone remodeling, such as collagen N-telopeptides, will also be measured. This response varies among individuals and may be related to handedness, menopausal status, function, etc. Detailed knowledge of how the forearm responds to disuse may also provide an extremely precise and useful model for advancing the prevention and treatment of osteoporosis due to immobilization, aging or space flight. Selected References Spadaro, J.A.: Mechanical and electrical interactions in bone remodeling. Bioelectromagnetics, 1996 in press. Spadaro, J.A., F.W. Werner, R.A Brenner, M.D. Fortino, L.A. Fay and W.T. Edwards: Cortical and trabecular bone contribute strength to the osteopenic distal radius. Journal of Orthopaedic Research 12:211-218, 1994. This profile was last updated on 09/29/2008 A short link is available for this profile: http://www.upstate.edu/faculty/?ID=spadaroj Back to Faculty Research @ Upstate Page |