Lee D C, Lim H K, McKay W B, Priebe M M, Holmes S A, Sherwood A M
Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106-4912, USA.
J Electromyogr Kinesiol. 2004 Jun;14(3):379-88. doi: 10.1016/j.jelekin.2003.10.006.
Individuals with incomplete spinal cord injuries (SCI) retain varying degrees of voluntary motor control. The complexity of the motor control system and the nature of the recording biophysics have inhibited efforts to develop objective measures of voluntary motor control. This paper proposes the definition and use of a voluntary response index (VRI) calculated from quantitative analysis of surface electromyographic (sEMG) data recorded during defined voluntary movement as a sensitive measure of voluntary motor control in such individuals. The VRI is comprised of two numeric values, one derived from the total muscle activity recorded for the voluntary motor task (magnitude), and the other from the sEMG distribution across the recorded muscles (similarity index (SI)). Calculated as a vector, the distribution of sEMG from the test subject is compared to the average vector calculated from sEMG recordings of the same motor task from 10 neurologically intact subjects in a protocol called brain motor control assessment (BMCA). To evaluate the stability of the VRI, a group of five healthy subjects were individually compared to the prototype, average healthy-subject vectors for all of the maneuvers. To evaluate the sensitivity of this method, the VRI was obtained from two SCI subjects participating in other research studies. One was undergoing supported treadmill ambulation training, and the other a controlled withdrawal of anti-spasticity medications. The supported treadmill training patient's VRI, calculated from pre- and post-training BMCA recordings, reflected the qualitative changes in sEMG patterns and functional improvement of motor control. The VRI of the patient followed by serial BMCA during medication withdrawal also reflected changes in the motor control as a result of changes in anti-spasticity medication. To validate this index for clinical use, serial studies using larger numbers of subjects with compromised motor control should be performed.
不完全性脊髓损伤（SCI）患者保留了不同程度的自主运动控制能力。运动控制系统的复杂性以及记录生物物理学的性质阻碍了开发自主运动控制客观测量方法的努力。本文提出了一种自主反应指数（VRI）的定义和应用，该指数通过对在特定自主运动期间记录的表面肌电图（sEMG）数据进行定量分析来计算，作为此类个体自主运动控制的敏感测量指标。VRI由两个数值组成，一个来自为自主运动任务记录的总肌肉活动（幅度），另一个来自记录肌肉上的sEMG分布（相似性指数（SI））。以向量形式计算，将测试对象的sEMG分布与在称为脑运动控制评估（BMCA）的方案中从10名神经功能正常的受试者的相同运动任务的sEMG记录中计算出的平均向量进行比较。为了评估VRI的稳定性，将一组五名健康受试者分别与所有动作的原型、平均健康受试者向量进行比较。为了评估该方法的敏感性，从参与其他研究的两名SCI受试者中获得了VRI。一名受试者正在接受辅助跑步机步行训练，另一名受试者正在接受抗痉挛药物的控制性撤药。从训练前和训练后的BMCA记录计算得出的接受辅助跑步机训练患者的VRI反映了sEMG模式的定性变化和运动控制的功能改善。在撤药期间进行连续BMCA的患者的VRI也反映了抗痉挛药物变化导致的运动控制变化。为了验证该指数在临床中的应用，应使用更多运动控制受损的受试者进行系列研究。
