目的　利用Motion capture运动捕捉及分析系统获得拇指对掌过程的6个自由度，尝试建立手功能检测的数字化方法。  方法    1例外形及功能均正常成人手, 在手掌背侧及各指皮肤上粘贴直径为5 mm荧光标志球。分别使拇指在自由状态、掌指关节、指间关节、掌指及指间关节固定，拇指与 2~5 指做最大范围对指运动，Motion capture运动捕捉及分析系统采集对掌运动的6个自由度，并对其6个自由度进行分析。  结果    Motion capture运动捕捉及分析系统获得了拇指对掌运动的6个自由度。通过统计描述分析，在拇指的掌指与指间关节未固定状态的对掌运动中，拇指与其余4指的对掌运动，线位移最大变化主要发生Y轴，角位移最大变化主要发生Z轴，同时其它2个轴的位移也发生相应变化。拇指在掌指与指间关节不同的固定状态下，线位移及角位移均有灵敏变化。  结论    Motion capture运动捕捉及分析系统能够采集拇指对掌的6个自由度，并可以明确拇指对掌运动过程的数字化规律，为建立以6 个自由度为基础手功能检查方法奠定了基础。

Objective　To explore the digital motion course of thumb opposition, through acquiring the six degrees of freedom using motion capture and analysis system, evaluate a digital hand motion examination method and provide digital basis for the virtual reality of hand function.　Methods　One had specimen from a normal adult without morphological and functional abnormalities, was marked on the back of palm and the dorsal surface of the finger bone by fluorescent balls. Thumb opposition was defined and performed six degrees of freedom using motion capture motion capture and analysis system.　Results　The data of six degrees of freedom of the thumb opposition were collected.  At the free states, thumb contacted with the rest of 4 fingers. The biggest changes of line displacement and angular displacement occurred mainly in Y-axis and Z-axis, respectively, followed by the different displacement changes of the another two axis accordingly. The changes of displacement reduced at the fixed state.　Conclusions　Motion capture motion capture and analysis system are sensitive tool to detect the six degrees of freedom of thumb opposition. The digital rules of thumb opposition will be able to achieve with six degrees of freedom, and provide the basis for virtual simulation of hand functions.