RESUMO
OBJECTIVES: The study validates a new computer mouse concept. The tested device is a small mouse with a pivoting pen-shaped handle. The hypothesis behind the design is the assumptions that the pen grip requires less static tension than the normal mouse grip and that fine-motor, high precision tasks normally are done with finger movements with forearm at rest. METHODS: Four muscles were monitored with electromyography (EMG) during work with a new mouse and with a traditional mouse. RESULTS: EMG activity was significant lower, in M. pronator teres--46%, M. extensor digitorum--46%, M. trapezius--69%, and M. levator scapulae--82%, during work with the new mouse as compared to the traditional mouse. CONCLUSION: Altering the design of the computer mouse can significantly reduce muscular tension.