PREDICTION OF TRUNK MUSCLE FORCES AND INTERNAL LOADS DURING FORWARD FLEXION ACTIVITIES

Abstract

Knowledge of load distribution among passive and active components of the human trunk during various occupational and sportive activities is essential to assess the risk of injury and to improve prevention, evaluation, and rehabilitation of spinal disorders. To solve the trunk redundancy toward determination of muscle forces and passive loads in forward bending tasks ± loads in hands, a novel synergistic kinematics-based approach coupled with a nonlinear finite element model are introduced. As a part of this study, trunk kinematics needed as input data and surface EMG activity of selected c:.bdominal/back muscles needed for validation of model are measured in normal subjects during isometric forward bending tasks. Predictions are in satisfactory agreement with in vivo measurements. The model proves promising in exercise and rehabilitation applications.