This study examined the influence of distributed external hand forces joint moments and muscle activation. Kinematics and forces were collected during multiple finger tasks while surface pressure was measured to create 3 force input models in OpenSim: (1) segment centre of mass (CM), (2) centre of pressure (CP), and (3) single point force on each digit (SP). CM and CP moment and activations were found equivalent. Distributed loading (CM and CP) produced lower moments and activation than SP. We found that internal loads are sensitive to external force distribution, supporting improved biofidelity via complex input forces in modelling the hand.
Chhiba et al. (Mon,) studied this question.