Evaluation of the finger and phalange froce distributions in pulling task

The pulling finger/phalange force distributions were investigated with various handles. Generally, oval handles required higher forces than double frustum handles in pulling task. The finger force distributions of the pulling task were similar to those of the gripping task. Middle (28%) and index (27.2%) were the strongest and little (20.8%) showed the lowest, followed by ring (23.9%). However, the phalange force distributions of the pulling task were different from the gripping task. Proximal (37.6%) produced the largest and middle (33.6%) also exerted more forces than distal (28.8%) phalanges. As the handle size increased, the forces of index and middle fingers showed increasing trends while ring and little fingers had decreasing trends. The phalange force was being moved more on distal phalanges than on proximal and middle phalanges. The understanding of force distributions may help to develop biomechanical finger models and to design hand tools for reducing related hand injuries.