Sit/stand workstation configuration affects upper extremity posture, muscle load and variability during computer mouse use

Musculoskeletal disorders related to computer use are known to affect the upper extremities. Computer workstation configuration influences upper extremity biomechanics. We examined siting, standing and non-optimal sitting workstation configurations, and analyzed posture, muscle activity and motor variability. We found that non-optimal sitting configuration caused more non-neutral postures and increased muscle load, particularly on the shoulders. Sitting and standing workstations resulted in similar median values for postures and muscle loads, but standing provided for larger variability. PCA analysis did not show any differences between configurations, but pointed to differences between subjects which could be divided into low and high variability groups. Being able to identify effects of nonoptimal configurations can lead to interventions to help decrease risks of developing musculoskeletal disorders.