Nowak Dennis A, Hermsdörfer Joachim
Department of Psychiatry III, University of Ulm, Leimgrubenweg 12-14, D-89075 Ulm, Germany.
Brain Res Rev. 2006 Jun;51(1):108-24. doi: 10.1016/j.brainresrev.2005.10.003. Epub 2005 Dec 13.
Impaired hand function is a frequent finding in movement disorders. The skilled control of prehensile finger forces is an essential feature of tool use in daily life. In healthy subjects, grip force is precisely adjusted to the mechanical object properties, such as weight and surface friction. Grip force is accurately scaled to be only a small amount higher than the minimum necessary to prevent a hand-held object from slipping. When an object is lifted and moved around in space, grip force is modulated in parallel with the movement-induced fluctuations in load. The absence of a temporal delay between grip and load force profiles implies that the central nervous system is able to predict the load variations before the intended manipulation. Sensory information is used to adjust the level of applied finger forces efficiently to the requirements of the mechanical object properties and the task at hand. The characteristics of impaired finger force control include inefficient grip force scaling and imprecision of the temporal coupling between grip and load force profiles. Here, we review the characteristics of deficient grip force behavior in movement disorders, e.g. Parkinson's disease, task-specific dystonia, Gille de la Tourette's syndrome and cerebellar disease. Grip force analysis is a highly sensitive method to document even subtle impairments of finger force control and may be used both as a diagnostic tool and for the objective evaluation of treatment in neurological movement disorders.
手部功能受损是运动障碍中常见的表现。对抓握手指力量进行熟练控制是日常生活中使用工具的一项基本特征。在健康受试者中，握力会根据物体的机械特性精确调整，比如重量和表面摩擦力。握力会精确调整到仅略高于防止手持物体滑落所需的最小力量。当物体在空间中被提起并移动时，握力会随着运动引起的负载波动而同步调节。握力和负载力曲线之间不存在时间延迟，这意味着中枢神经系统能够在预期操作之前预测负载变化。感觉信息被用于根据物体的机械特性和手头任务的要求，有效地调整施加的手指力量水平。手指力量控制受损的特征包括握力调整效率低下以及握力和负载力曲线之间时间耦合的不精确性。在此，我们回顾运动障碍（如帕金森病、特定任务性肌张力障碍、 Gilles de la Tourette综合征和小脑疾病）中握力行为缺陷的特征。握力分析是一种高度敏感的方法，可用于记录手指力量控制的细微损伤，并且可作为诊断工具以及用于对神经运动障碍治疗效果的客观评估。
