- 學位論文
使用不同厚度的電腦鍵盤對前臂及肩部肌電流之影響
The effect on forearm and shoulder muscle activity in using different thickness computer keyboards
摘要
國內外以有許多人體工學的學者致力於研究鍵盤外型對手腕動作以及上肢肌肉負荷的影響，在我們的文獻回顧中沒有相關於鍵盤厚度的研究，然而隨著科技進步，市面上販售越來越多款薄造型的鍵盤，因此本研究的目的是利用表面電極片與雙軸角度規去量化鍵盤厚度對於手腕姿勢以及上肢肌肉的影響。 有二十八位受試者自願參與本次實驗，並且每位受試者進行同樣的複製文件的工作。在打字的過程中，兩側尺側伸腕肌(ECU)、伸指肌(ED)和斜方肌(Trap)的機電流以及手腕姿勢分別由表面電極片以及雙軸角度規採集並紀錄。 本實驗中，以T0與NB鍵盤模擬零厚度的鍵盤與筆記型電腦的鍵盤，在使用T0和NB鍵盤時分別顯現出最小的手腕尺骨方向偏移與最小的手腕伸屈，並且使用越厚的鍵盤將會造成越多的手腕伸屈及尺骨方向偏移，也就是手腕將會越偏離自然的姿勢，相類似的趨勢也發生於前臂肌肉的結果上，因此我們可以合理的推論，使用零厚度或是筆記型鍵盤打字將會降低上肢骨骼肌肉不適與手腕隧道症的風險。這樣的結果將可以作為廠商將來在設計鍵盤時的依據或是消費者在購買鍵盤時的建議。
並列摘要
Several ergonomics researches had devoted to treat the effect of the shape of a keyboard on working posture and upper extremity muscle activity. There was no study associated with computer keyboard thickness from our survey literatures. The purpose of this study was to examine the effect of computer keyboard thickness on forearm muscle activity and wrist posture. In this experiment 28 subjects participated voluntarily and performed the same copy typing task while using four different thickness keyboards separately. During typing, the muscle activity of the bilateral extensor carpi ulnaris (ECU), extensor digitorum communis (ED) and upper trapezius (Trap) muscles, and the wrist postures were recorded by surface electrodes and twin axis electrogoniometers respectively. The keyboards T0 and NB were simulated as zero height keyboards and notebook keyboards separately. The use of the keyboards T0 and NB resulted in the lowest mean ulnar deviation of 11.59° and lowest mean wrist extension of 17.55° respectively. Moreover, the thicker keyboard used, the more wrist deviation from the neutral position was. The tendencies of the ECU and ED were similar to that of the wrist extension. From the above, using the zero thickness keyboard or the notebook keyboard would decrease the risks of musculoskeletal symptoms of upper extremity and carpal tunnel syndrome. The results may make recommendations for users to pick out and purchase keyboards.