Walking Biomechanics and Bone Density in Healthy, Elderly Adults

Principal Investigator: Gary S. Beaupré, PhD

Co-Investigators: Thomas P. Andriacchi, PhD; Nicholas J. Giori, MD; B. Jenny Kiratli, PhD; Katherine A. Boyer, PhD; Joe Guerricabeitia, MS; Barbara Elspas, MPH; and S. Williams, BS

Objective: In this study we hypothesize that the differences in habitual walking activity lead to differences in bone density at the proximal femur. The specific objectives of this project are to determine experimentally derived relationships between walking characteristics and bone mineral density at the hip in middle-aged and older adults. These correlations will be evaluated in the context of a theoretical biomechanical framework to examine causal relationships between gait characteristics and skeletal loading and between skeletal loading and bone mineral density. It is anticipated that synthesis of our experimental and theoretical results will allow us to predict the potential beneficial effects of specific osteoporosis countermeasures such as increasing walking speed and increasing habitual walking activity. In this study we will use experimental and computational approaches to answer the following key questions:

• What are the experimentally determined relationships between measured gait parameters (such as self-selected walking speed and peak ground reaction force magnitude during the stance phase of gait) and bone mineral density at the hip?

• How well can computer models predict bone density in healthy adults as a function of their average daily physical activity and ground reaction forces or hip joint contact force determined from gait analysis?

Milestones

• Testing has been completed for 21 subjects.
• Recruitment and testing are proceeding at a rate of 2 to 4 subjects per week.

Publication

Boyer KA, Beaupré GS, Andriacchi TP: Gender differences in hip joint kinetics in healthy older walkers as a consideration in treatment interventions for osteoporosis. Trans Orthop Res Soc, 32:1825, 2007.

Funding Source: Department of Veterans Affairs – Merit Review