Relationship between alignment and kinematic and kinetic measures of the knee of osteoarthritic elderly subjects in level walking

Eleven osteoarthritic elderly subjects were tested to analyse the relationships between static radiographic alignment and dynamic kinematic and kinetic measures at the knee in gait. A standard precision radiograph procedure (QPR) was used to measure the static lower limb alignment in two planes and a 3D optoelectronic system was used to measure the biomechanical performance of the knee in level walking. Relationships were calculated between the static radiographic angular measures and the dynamic knee angular measures, dynamic knee joint forces, and dynamic knee moments of force during gait. The results indicated that there was not a close relationship between lower limb alignment and the force estimates in gait. However, a closer relationship was observed between QPR parameters, dynamic knee joint angles, and joint moments in gait, implying that complex interrelationships may exist between static alignment, dynamic alignment, and dynamic kinetic measures. These findings suggest that the static alignment measures associated with both the kinematic and kinetic measures should be combined to better explain the biomechanical changes at the knee joint.