Changes in posture through the use of simple inclines with notebook computers placed on a standard desk

摘要

This study evaluated the effects of inclining a notebook computer on upper extremity postures. Fifteen adults performed a standardized computing task on a notebook placed flat on a desk (DESK), inclined at 12° (INC12) and inclined at 25° (INC25) while a motion analysis system measured upper extremity postures. Compared to the DESK, the inclines reduced forward head tilt approximately 3° per incline level while neck flexion was reduced 2° per level. Wrist extension was increased on average 5° and 12° for the INC12 and INC25 configurations, respectively. In conclusion, the inclines led to a tradeoff between adverse wrist extension and improved head and neck posture. We recommend the 12° incline if tasks do not involve a high degree of internal keyboard and mouse use (i.e. reading) while the 25° incline is not recommended if the internal input devices are used.