書寫工作中，針對前臂及手部肌肉而言理想的原子筆管徑之研究

The optimum diameter of ballpoint pens for hand and forearm muscle activity in writing tasks

黃科維(Ko-Wei Huang)

指導教授 ： 陳漢明

國立臺灣大學/工學院/機械工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.02847

摘要

原子筆在手寫工作環境中扮演著極重要的角色，但過去並沒有太多針對原子筆書寫工作的研究。雖然隨著電腦的普及化，手寫工作的時間相對減少，但筆仍然是不可或缺的民生用品之一，本次實驗的目的即在於探討不同粗細的原子筆對於人體手部及前臂肌肉的影響。
有二十五位受試者自願參與本次實驗，受試者於實驗前三天禁止高強度的運動，避免肌肉疲勞對實驗結果造成變異；每位受試者皆進行同樣的書寫工作。在寫字的過程中，兩側尺側伸腕肌(ECU)、伸指肌(ED)、上肢橈側屈腕肌(FCR)、屈拇短肌(FPB)、第一背側骨間肌(FDI)和斜方肌(Trap)的肌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，我們製作了8mm~16mm五支不同管徑的原子筆，以D8, D10, D12, D14和D16 來代稱，並且也製作了問卷紀錄受測者主觀的喜好供為參考。實驗發現除了斜方肌外，對於其餘五條肌肉12mm的原子筆皆顯現出最小的肌肉活性，因此我們可以合理的推論，以本次實驗的設計而言直徑為12mm的原子筆為最佳之管徑；此外根據問卷的調查也顯示了類似的結果。而角度規紀錄的結果則顯示，本次實驗的管徑分佈並不會對書寫的姿勢有明顯的影響。
根據本實驗的結果，除了個人的書寫習慣，最佳的原子筆管徑應和手指的長短及粗細有著密切關聯，適當的管徑將可以降低手部和前臂因長時間進行書寫工作而造成的不適。這樣的結果將可以作為廠商將來在設計原子筆的依據，或是消費者在購買原子筆時的建議。

關鍵字

原子筆管徑 ； 表面電極片 ； 手腕姿勢 ； 表面肌電流

並列摘要

Prolonged use of pens may cause musculoskeletal discomfort and symptoms in forearms and shoulders. Writing with different diameter ballpoint pens may have various effects on forearm and finger muscle activity. Each of the twenty-five subjects performed the same writing task with each of the five different diameter pens. Extensor carpi ulnaris, extensor digitorum, flexor carpi radialis, flexor pollicis brevis, first dorsal interosseous and upper trapezius muscle activity were recorded by surface electromyography. The wrist postures were registered by an electrogoniometer, and then the recorded data were analyzed with the one-way ANOVA. Extensor digitorum, flexor carpi radialis and flexor pollicis brevis muscle activity were lowest when using the ballpoint pen with 12mm diameter. A recommendation resulting from this study for writing work is that using a ballpoint pen with a suitable diameter can provide the user less forearm muscle activity so the risk of musculoskeletal disorders may be reduced. Furthermore, some forearm muscle activity in using the ballpoint pen of 14mm diameter were even lower than that in using the ballpoint pen of 10mm diameter, and therefore the ballpoint pen of 14mm diameter might be another good choice for writing work.

並列關鍵字

Pen diameter ； Surface electromyography ； electrogoniometer ； muscle activity

參考文獻

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