Imu-derived metrics of kinematics and kinetics in aging and knee osteoarthritis gait

Aged or knee osteoarthritis gait is commonly assessed via optical motion capture (MoCap). However, tracking changes or identifying deficits in gait in the real-world setting is difficult to accomplish with MoCap. In this study, we tested the ability of inertial measurement units (IMUs) to capture gait kinematics similarly to MoCap, and we examined correlations between MoCap joint powers and IMU segment velocities in groups differing by age and knee osteoarthritis. IMU and MoCap kinematics were not different and both identified between-group differences. Correlations between MoCap powers and IMU angular velocities were moderate to strong. These results suggest that IMUs may be suitable to assess gait or track changes in joint powers from a baseline assessment.