Knee osteoarthritis (OA) is a painful and debilitating disease that contributes significantly to functional limitations and disability, negatively impacting physical function and quality of life of an estimated 20 million Americans. Normal activities of daily living (ADLs), such as climbing stairs, become a growing burden for those who suffer from knee OA. Surprisingly, few studies have examined stair climbing in osteoarthritic knees. Therefore, to better understand joint mechanics in people with knee OA we will examine the hip, knee and ankle joint kinematics and kinetics during stair ascent and descent in 30 subjects with knee OA and 30 age, height, mass and gender-matched healthy controls using a 3-D motion analysis system. Additionally radiographs and WOMAC osteoarthritis index will also be used to assess the extent of knee OA. A repeated measures MANOVA will be used to test for significant differences in lower extremity joint kinematics and kinetics between the subjects. We hypothesize that there will be decreased knee range of motion and external knee moments in knee OA subjects versus healthy subjects. Additionally, we hypothesize that knee OA subjects will experience increased hip and ankle range of motion and increased external hip and ankle moments compared to healthy subjects during stair climbing. Further we hypothesize that knee OA subjects will significantly compensate greatly for these differences with increased range of motion and external moments present in the contra-lateral joints. Understanding the knee joint mechanics in people with knee OA is essential for optimal management and rehabilitation to improve normal ADLs.
Specific Aims: 1.To compare the hip, knee and ankle joint kinematics and kinetics during stair ascent between knee OA subjects and age, sex, height, and body mass matched healthy controls. 2.To compare the hip, knee and ankle joint kinematics and kinetics during stair descent between knee OA subjects and age, sex, height, and body mass matched healthy controls. Research Hypotheses: 1.Increased angles and net moments in the sagittal and frontal planes will be present at foot strike, peak support and toe off in the hip and ankle joints in knee OA subjects compared to healthy matched controls during stair ascent and descent. 2.Time of peak angle during support and swing in the sagittal and frontal planes will be later in the gait cycle in knee OA subjects compared to healthy matched controls during stair ascent and descent.
Principal Investigator: Charlie Hicks-Little
Department: Exercise And Sport Science