The spiral drawing task is a representative clinical test used to assess essential tremor. Many clinicians have used spirography to assess through visual rating of the drawings. We quantitatively investigated the clinical characteristics of action tremors during spiral drawing tasks using 3-axis gyro sensors. Eighteen essential tremor patients with sensors attached to their forefinger, dorsum of the hand, and forearm participated in a spiral drawing test. As quantitative variables, the average speed, maximum frequency and maximum power were derived from the gyro sensor signals. The average speed and maximum power were also logarithmically transformed. Two-way repeated measures analysis of variance (ANOVA) with tremor direction and joint (attachment location) as independent factors was performed to evaluate the main and interactive effects of direction and joint. Also, Spearman’s correlation analysis was performed to evaluate the relationship between the quantitative variables and visual rating scores. The average speed showed a significant main effect of direction (P<0.01). Logarithmic variables showed interactive effects (P<0.01) as well as main effects (P<0.01). The interactive effects were attributed to no significant difference among the joints particularly in the roll direction (P>0.05). The logarithmic variables of roll direction were significantly greater than that of the other directions (P<0.001). Also, the quantitative variables were moderately correlated with visual rating scores (r=0.48−0.73, P<0.05). These results indicate that kinetic tremor during spiral drawing mainly appears in the roll direction and may contribute to the determination of sensor location and direction for continuous monitoring of patients with essential tremor.

中文翻译：

---

使用陀螺仪传感器对临床螺旋绘图任务中的特发性震颤进行定量分析

螺旋绘图任务是用于评估特发性震颤的代表性临床测试。许多临床医生已经使用肺活量图通过对图纸的视觉评级来进行评估。我们使用 3 轴陀螺仪传感器定量研究了螺旋绘图任务期间动作性震颤的临床特征。18 名特发性震颤患者的食指、手背和前臂都装有传感器，他们参加了螺旋绘图测试。作为定量变量，平均速度、最大频率和最大功率来自陀螺传感器信号。平均速度和最大功率也进行了对数变换。以震颤方向和关节（附着位置）为独立因素进行双向重复测量方差分析（ANOVA），以评估方向和关节的主要和交互作用。此外，进行 Spearman 相关分析以评估定量变量和视觉评分之间的关​​系。平均速度显示出显着的方向主效应（磷<0.01）。对数变量表现出交互效应（磷<0.01) 以及主效应 (磷<0.01）。交互效果归因于关节之间没有显着差异，特别是在滚动方向上（磷>0.05）。侧倾方向的对数变量显着大于其他方向（磷<0.001）。此外，定量变量与视觉评分中度相关（r=0.48-0.73,磷<0.05）。这些结果表明，螺旋拉拔过程中的运动震颤主要出现在滚动方向，可能有助于确定传感器位置和方向，以连续监测特发性震颤患者。