Grant: Team Grant: Physical Activity, Mobility and Health (full application)

There is evidence that certain types of physical activity cause hip osteoarthritis (OA). OA occurs when the cartilage (the gristle that lines the ends of the bone) is damaged. OA is the most common form of hip arthritis and responsible for more than 90% of hip replacements (more than 21,000 hip replacements are done per year in Canada). Recently, subtle deformities of the hip have been linked to hip OA. It is believed that certain types of physical activity such as hockey, soccer and bicycling combine with the deformity to cause hip damage. The goal of this CIHR team is to show how physical activity while interacting with one or more subtle deformities can cause cartilage damage and eventually OA. We will determine the frequency of the deformities in the population, compare the frequency in groups thought to have a lower frequency (Chinese) or higher frequency (Aboriginal Peoples) of OA compared to Caucasians and see if physical activity over one's lifetime is important in causing hip pain and eventually hip OA. In addition, we will: 1) See how the physical motion and the deformity combine to damage cartilage using Canada's only magnetic resonance imaging (MRI) machine that allows testing with the person standing up and with movement; 2) Use new techniques that show changes in the cartilage even though it is normal on a regular MRI; and, 3) Get the results out to Canadians better than has ever been done before. These questions will be addressed by a collaborative team of researchers from four medical specialties (orthopaedics, rheumatology, physiotherapy, radiology), six research disciplines (basic and clinical sciences, population health, epidemiology, biostatistics, health services research and knowledge translation), as well as stakeholders from the arthritis community. This research program will generate the new knowledge needed for major breakthroughs in the prevention, detection and treatment of hip OA.