抄録
Joint torque in humans is affected by such factors as optimum muscle and moment arm length. The torque exerted varies with the static joint angle, and the differences are generally called joint angle-torque characteristics, which vary with the type of joint and direction of joint motion. These characteristics are therefore regarded as important factors when considering the most appropriate postures for specific exertion in clinical practice or the biomechanical field. Several studies on angle-torque characteristics have been performed on a small number of subjects, but limited data has been obtained from studies performed on large number of subjects, let alone the assessment of the impact of such characteristics on the differences in the joint angle of extremity joints. Accordingly, in the present study, we investigated angle-torque characteristics of extremity joints based on the patient characteristic data of 711 healthy Japanese individuals obtained between 2001 and 2002 obtained from the National Institute of Technology and Evaluation. The results revealed characteristic peaks in the joint-torque curves near the center of the measurement range for elbow flexion, shoulder flexion, shoulder extension, and knee extension. The peaks were most evident in elbow flexion. The joint torque values in elbow extension, knee flexion, hip flexion, and extension characteristically peaked at either end of the measurement range. In addition, the results of a two-way ANOVA performed on joint torque with generation and joint angle as independent factors revealed that the joint torque was affected by generational differences. This result suggests that it is impossible to achieve adequate accuracy in the fields where joint angle-torque characteristics are used such as product design without the data for generational differences.
