Principal Investigator: Carolynn Patten, PhD, PT Project Staff: Jody M. Dozono, MPT; B. Jenny Kiratli, PhD; and Christopher R. Jacobs, PhD Project Category: Stroke - 2004 Objective: The goal of this BAJR Center pilot project is to study effects of exercise-based therapeutic interventions on bone remodeling in persons with post-stroke hemiparesis. Stroke is the leading cause of physical disability in western industrialized nations predominantly affecting persons sixty or more years of age. It can be hypothesized that age-related compromise to bone integrity coupled with the profound disabling influence of stroke, would accelerate bone loss and lead to secondary pathologies including osteoporosis and high risk of fractures. This pilot project seeks to determine the extent to which high-intensity exercise-based therapies intended to restore neuromuscular function in hemiparetic persons affect bone remodeling. The literature reports osteogenic effects of eccentric exercise (e.g., muscle lengthening contractions) in healthy adults. We hypothesize therefore that therapies involving eccentric resistance exercise (i.e., controlling an externally imposed load, gait) will produce physiologically significant osteogenic effects in hemiparetic adults. Research Plan and Methods: Hemiparetic subjects (6-18 months post-stroke) who enroll in the project "Therapeutic Effects on Neuromuscular Function in Post-stroke Hemiparesis" (C. Patten, P.I.) will undergo parallel studies of bone integrity and bone remodeling. Subjects will receive DXA scans (whole body and proximal femur) at baseline, following the two-month clinical intervention, and at follow up study one-year post-intervention. These studies are conducted in conjunction with Dr. B. Jenny Kiratli in the VA Palo Alto Clinical center. Blood samples will also be obtained at the same time points and analyzed post-hoc for key markers of osteoblastic and osteoclastic activity. Progress Report and Findings to Date: Twenty subjects who participated in the "Therapeutic Effects" projects have been recruited and are being followed. DXA scans, and blood and urine samples are being obtained to track biologic markers of bone remodeling following therapeutic intervention. Research Plan for the Next Year: We intend to initiate analysis of biochemical markers at the completion of patient treatment in May 2005. Funding Source: Center Core funding Funding Status: Active |
