Schneider A S, Fürholzer W, Marquardt C, Hermsdörfer J
Schön Klinik München Harlaching, Munich, Germany; Clinical Neuropsychology Research Group (EKN), Clinic of Neuropsychology, Hospital München-Bogenhausen, Germany.
Clinical Neuropsychology Research Group (EKN), Clinic of Neuropsychology, Hospital München-Bogenhausen, Germany.
Clin Neurophysiol. 2014 Apr;125(4):786-797. doi: 10.1016/j.clinph.2013.09.043. Epub 2013 Nov 13.
Writer's cramp is defined as a task specific focal dystonia generating hypertonic muscle co-contractions during handwriting resulting in impaired writing performance and exaggerated finger force. However, little is known about the generalisation of grip force across tasks others than writing. The aim of the study was to directly compare regulation of grip forces during handwriting with force regulation in other fine-motor tasks in patients and control subjects.
Handwriting, lifting and cyclic movements of a grasped object were investigated in 21 patients and 14 controls. The applied forces were registered in all three tasks and compared between groups and tasks. In addition, task-specific measures of fine-motor skill were assessed.
As expected, patients generated exaggerated forces during handwriting compared to control subjects. However there were no statistically significant group differences during lifting and cyclic movements. The control group revealed a generalisation of grip forces across manual tasks whereas in patients there was no such correlation.
We conclude that increased finger forces during handwriting are a task-specific phenomenon that does not necessarily generalise to other fine-motor tasks.
Force control of patients with writer's cramp in handwriting and other fine-motor tasks is characterised by individualised control strategies.
书写痉挛被定义为一种特定任务的局灶性肌张力障碍，在书写过程中产生高张力的肌肉共同收缩，导致书写表现受损和手指力量过度增大。然而，除书写外，对于抓握力在其他任务中的普遍性了解甚少。本研究的目的是直接比较患者和对照受试者在书写过程中抓握力的调节与其他精细运动任务中的力量调节。
对21例患者和14名对照者进行了书写、提起和抓握物体的循环运动研究。记录了所有三项任务中施加的力，并在组间和任务间进行了比较。此外，还评估了特定任务的精细运动技能指标。
正如预期的那样，与对照受试者相比，患者在书写过程中产生了过度的力量。然而，在提起和循环运动过程中，两组之间没有统计学上的显著差异。对照组显示抓握力在各种手动任务中具有普遍性，而患者则没有这种相关性。
我们得出结论，书写过程中手指力量增加是一种特定任务的现象，不一定会推广到其他精细运动任务中。
书写痉挛患者在书写和其他精细运动任务中的力量控制具有个体化的控制策略。
