Classic galactosemia (CG) is a rare inborn error of metabolism that results from profound deficiency of galactose-1-P uridylyltransferase (GALT). Despite early detection and rapid and lifelong dietary restriction of galactose, which is the current standard of care, most patients grow to experience a broad range of complications that can include motor difficulties. The goal of this study was to characterize hand fine motor control deficit among children and adults with classic galactosemia (CG). Specifically, we used Neuroglyphics software to collect digital Archimedes spiral drawings on a touch screen from 57 volunteers with CG (cases) and 80 controls. Hand fine motor control was scored as root mean square (RMS) of spirals drawn relative to an idealized template. Presence of tremor was defined as a peak in periodicity of changes in drawing speed or direction in the 4-8 Hz range. We observed a highly significant difference (P < .001) in RMS scores between cases and controls, with almost 51% of cases showing at least 1 of 4 spirals scoring outside the 95th percentile for controls. The corresponding prevalence for controls was 10%. Similarly, more than 35% of cases, and almost 14% of controls, showed at least 1 of 4 spirals with a tremor amplitude above the 95th % cutoff for controls. Our results both confirm and extend what is known about hand fine motor control deficit among children and adults with CG and establish digital assessment as a useful approach to quantify this outcome.

中文翻译：

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经典半乳糖血症的手部精细运动控制

经典半乳糖血症 (CG) 是一种罕见的先天性代谢错误，由 galactose-1-P uridylyltransferase (GALT) 的严重缺乏引起。尽管半乳糖的早期发现和快速和终生的饮食限制是目前的护理标准，但大多数患者会经历广泛的并发症，包括运动困难。本研究的目的是描述患有经典半乳糖血症 (CG) 的儿童和成人的手部精细运动控制缺陷。具体来说，我们使用 Neuroglyphics 软件从 57 名具有 CG（案例）和 80 个控件的志愿者的触摸屏上收集数字阿基米德螺旋图。手部精细运动控制评分为相对于理想化模板绘制的螺旋线的均方根 (RMS)。震颤的存在被定义为在 4-8 Hz 范围内绘制速度或方向变化的周期性峰值。我们观察到非常显着的差异（P  < .001) 在病例和对照组之间的 RMS 分数，几乎 51% 的病例显示 4 个螺旋中的至少 1 个在对照组的第 95 个百分位之外得分。对照组的相应患病率为 10%。同样，超过 35% 的病例和近 14% 的对照组显示 4 个螺旋中至少有 1 个的震颤幅度高于对照组的 95% 截止值。我们的结果证实并扩展了对患有 CG 的儿童和成人手部精细运动控制缺陷的了解，并将数字评估确立为量化这一结果的有用方法。