Jin Sangeun, Kim Jaehyuk, Kim Daemin
Department of Industrial Engineering, The Human and Safety Engineering Laboratory, Pusan National University, Busan, Republic of Korea.
The Human Mechatronics Engineering Laboratory, Division of Mechatronics Engineering, Dongseo University, Busan, Republic of Korea.
Work. 2020;65(3):581-589. doi: 10.3233/WOR-203112.
The use of tablet during the office work is on the rise, but the biomechanical response of tablet use under various sitting postures is not well understood.
This study quantitatively measured changes in trunk kinematics under three sitting conditions (raised leg, neutral leg, and lowered leg) while using a tablet.
Fifteen participants were asked to sit on a chair with three different postures while staring at a handheld tablet or gazing straight ahead with a bare hand, and the head flexion, lumbar flexion and trunk inclination were captured with electrical goniometers.
The results revealed significantly less lumbar flexion (12.8%) and trunk inclination (28.0%) while using the tablet compared to the empty hand condition (p < 0.001), but at a significant cost of increased head flexion (90.8%; p < 0.001). Further, while using the tablet, participants showed less head flexion in the raised leg condition (p < 0.001) than in the others (9.7% and 7.5%, respectively), but larger trunk inclination and lumbar flexion were required (p < 0.001 in both).
Collectively, the lower extremity sitting posture significantly changed the way to observe the tablet by adopting more head flexion in neutral and lowered leg conditions or more trunk flexion in raised leg condition.
办公期间平板电脑的使用呈上升趋势，但不同坐姿下使用平板电脑的生物力学反应尚不清楚。
本研究定量测量了在使用平板电脑时三种坐姿（抬腿、腿自然下垂、放低腿）下躯干运动学的变化。
15名参与者被要求以三种不同姿势坐在椅子上，同时盯着手持平板电脑或空手直视前方，用电角度计记录头部前屈、腰椎前屈和躯干倾斜情况。
结果显示，与空手状态相比，使用平板电脑时腰椎前屈（12.8%）和躯干倾斜（28.0%）显著减少（p< 0.001），但代价是头部前屈显著增加（90.8%；p< 0.001）。此外，使用平板电脑时，参与者在抬腿状态下的头部前屈比其他状态少（p< 0.001）（分别为9.7%和7.5%），但需要更大的躯干倾斜和腰椎前屈（两者均p< 0.001）。
总的来说，下肢坐姿显著改变了观察平板电脑的方式，在腿自然下垂和放低腿状态下采用更多的头部前屈，在抬腿状态下采用更多的躯干前屈。
