本研究著重於在開罐動作中(包括了用力抓握動作及精確抓捏動作)，拇指的生物力學分析。本研究第一部份將利用自行設計的罐子模擬器(罐子直徑8.3cm，內部結構包含有小型六軸荷重感測器及扭力計)量測開罐動作(包括用力抓握及精確抓捏)時，拇指對罐蓋所施與的力量及扭矩，並計算拇指在開罐時所佔之貢獻度。第二部份則是建立拇指肌肉力學模型，以最佳化方法估計在開罐動作中拇指主要活動肌肉及關節的受力情況。
　　共有十位手功能正常無受傷的受試者參加本實驗。結果顯示，開罐動作時，拇指作用於罐蓋的總合力平均值為46.2N，拇指扭矩平均為0.58 N-m，總扭矩平均為1.8N-m，拇指在扭矩的貢獻度上約佔手的30%~ 35%。
　　在經拇指生物肌肉模型計算後，得在開罐動作中肌肉總合力平均約為240.7N (其中主要作用肌肉為FPL=67.5N, ADD=58.5N, FPB=38.9N, APB=20.5N, OPP=37.3N)。在拇指一單位施力下，統計結果顯示用力抓握動作時肌肉所需總合力小於精確抓捏動作時肌肉所需總合力，此表示用力抓握動作為一較有效率的動作。
　　在拇指各關節中，腕掌關節(CMC joint)所受總合力為最大，平均約221.5N，此約為拇指施力值之4.8倍。其次為掌指骨關節(MCP joint)，所受總合力約為153N，約為拇指施力值之3.3倍。最小為指骨關節(IP joint)，此關節所受合力約為69N，約為拇指施力值之1.5倍。

　　The study focused on the biomechanical analysis of the thumb during the activities of jar opening (including activities of power grip and precision handling). The first part of this study was to measure the forces and torques of the thumb applied to the jar lid using a custom designed jar simulator (the jar’s diameter was 8.3cm) equipped with a six-axis load cell and a torque sensor. The second part of this study was to develop a three-dimensional biomechanical model of the thumb in order to calculate joint loads and muscle forces during jar opening.
　　Ten healthy subjects participated in this study. The results showed that the average resultant forces applied to the jar lid were 46.2N, the average twisting torques from the thumb were 0.58N-m, the average twisting torques from the hand to open a jar were 1.8N-m, and the average contribution of the thumb was about 30% ~ 35%.
　　During jar opening, the average total muscle forces were 240.7N (the major active muscles were FPL=67.5N, FPB=38.9N, APB=20.5N, ADP=58.5N, OPP=37.3N). The activity of precision handling needed the large muscle force than the activity of power grip for each one unit external force applied to the thumb. This meant “precision handling” was more energy cost than “power grip”.
　　It bore 221.5N at the carpometacarpal (CMC) joint, about 4.8 times the applied forces of the thumb, 153N at he metacarpophalangeal (MCP) joint, about 3.3 times the applied forces of the thumb and 69N at the interphalangeal (IP) joint, about 1.5 times the applied forces of the thumb.

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