Lebiedowska Maria K, Fisk John R
Functional &Applied Biomechanics Section, National Institutes of Health, Rehabilitation Medicine Department, BLDG. 10, CRC, RM-1-1469, 10 Center Drive, MSC 1604, Bethesda, MD 20892-1604, USA.
J Neurosci Methods. 2009 May 15;179(2):323-30. doi: 10.1016/j.jneumeth.2009.02.005. Epub 2009 Feb 28.
The aims of the study were to determine by a portable method (1) whether velocity-dependent changes in knee resistance in patients with spastic paresis differ from those in non-disabled subjects, and (2) whether biomechanical measures of resistance can differentiate between neural and other factors that contribute to hypertonia (increased resistance). Biomechanical (hand-hold dynamometer, electrogoniometer) and bioelectrical (EMG) measures of resistance were evaluated under static (slow stretch) and dynamic (fast stretch) conditions in twenty patients with hypertonia and 19 non-disabled subjects. Measures calculated for non-disabled subjects (control limbs) were compared to those calculated for patients (spastic limbs). Biomechanical measures of resistance did not differ strongly between groups of spastic and control limbs and between spastic limbs having different origins of knee hypertonia (neural vs. other), due to substantial variability. In contrary the static and dynamic bioelectrical measures of muscles activation were substantially larger in spastic limbs than in control limbs (p<0.05). The variability of biomechanical measures of resistance was due to varied patterns of muscle activation in response to stretch. We concluded that the biomechanical measures of hypertonia did not discriminate spastic patients from non-disabled subjects. To classify various types of knee hypertonia, the portable method should include not only analysis of biomechanical but also EMG characteristics of hypertonia. It is expected that the functional status of patients would be better predicted using clinical and quantitative measures of impairment if different classes of hypertonia (defined by different patterns of activation) were analyzed separately rather than analyzing the heterogeneous patient population as a whole.
（1）痉挛性麻痹患者膝关节阻力的速度依赖性变化是否与非残疾受试者不同；（2）阻力的生物力学测量是否能够区分导致张力亢进（阻力增加）的神经因素和其他因素。在静态（缓慢拉伸）和动态（快速拉伸）条件下，对20名张力亢进患者和19名非残疾受试者的阻力进行了生物力学（手持测力计、电子测角仪）和生物电（肌电图）测量。将非残疾受试者（对照肢体）的测量结果与患者（痉挛肢体）的测量结果进行比较。由于存在很大的变异性，痉挛肢体组和对照肢体组之间以及膝关节张力亢进起源不同（神经源性与其他原因）的痉挛肢体之间，阻力的生物力学测量结果差异并不显著。相反，痉挛肢体的肌肉激活的静态和动态生物电测量结果显著高于对照肢体（p<0.05）。阻力生物力学测量的变异性是由于肌肉对拉伸反应的激活模式不同所致。我们得出结论，张力亢进的生物力学测量无法区分痉挛患者和非残疾受试者。为了对各种类型的膝关节张力亢进进行分类，便携式方法不仅应包括对张力亢进生物力学的分析，还应包括肌电图特征分析。如果分别分析不同类型的张力亢进（由不同的激活模式定义），而不是将异质性患者群体作为一个整体进行分析，预计使用临床和定量损伤测量方法能更好地预测患者的功能状态。
