Lang Catherine E, Wagner Joanne M, Bastian Amy J, Hu Qingli, Edwards Dorothy F, Sahrmann Shirley A, Dromerick Alexander W
Program in Physical Therapy, Washington University, 4444 Forest Park Blvd, Campus Box 8502, St Louis, MO, USA.
Exp Brain Res. 2005 Sep;166(1):126-36. doi: 10.1007/s00221-005-2350-6. Epub 2005 Jul 14.
We studied how acute hemiparesis affects the ability to perform purposeful movements of proximal versus distal upper extremity segments. Given the gradient of corticospinal input to the spinal motoneuron pools, we postulated that movement performance requiring distal segment control (grasping) should be more impaired than movement performance requiring proximal segment control (reaching) in people with hemiparesis. We tested subjects with acute hemiparesis and control subjects performing reach and reach-to-grasp movements. Three characteristics of movement performance were quantified for each movement: speed, accuracy, and efficiency. For the reach, we calculated peak wrist velocity, endpoint error, and reach path ratio. For the grasp, we calculated peak aperture rate, aperture at touch, and aperture path ratio. To evaluate the relative deficits in reaching versus grasping, performance measures were converted to z-scores using control group means and standard deviations. For both the movements, movement times were longer and performance was more variable in the hemiparetic group compared to the control group. Hemiparetic z-scores indicated that relative deficits in movement speed were small in the two movements, with deficits in grasp being slightly greater than deficits in reach. Relative deficits in accuracy showed a trend for being larger in the reach compared to the grasp, but this difference did not reach statistical significance. In contrast, relative deficits in efficiency were larger in the grasp compared to the reach, with reaching efficiency near the range of normal performance. When considering data across all three movement characteristics, the ability to perform a purposeful movement with the distal segments was not clearly more disrupted than the ability to perform a purposeful movement with the proximal segments in people with acute hemiparesis.
我们研究了急性偏瘫如何影响上肢近端与远端节段进行有目的运动的能力。鉴于皮质脊髓输入到脊髓运动神经元池的梯度,我们推测,在偏瘫患者中,需要控制远端节段的运动表现(抓握)应比需要控制近端节段的运动表现(伸展)受损更严重。我们测试了急性偏瘫患者和对照组受试者进行伸展及伸展-抓握运动的情况。对每个运动的运动表现的三个特征进行了量化:速度、准确性和效率。对于伸展运动,我们计算了腕部峰值速度、终点误差和伸展路径比率。对于抓握运动,我们计算了峰值开口率、接触时的开口度和开口路径比率。为了评估伸展与抓握运动中的相对缺陷,使用对照组的均值和标准差将表现指标转换为z分数。与对照组相比,偏瘫组的两个运动的运动时间都更长,表现也更具变异性。偏瘫组的z分数表明,两个运动中运动速度的相对缺陷较小,抓握运动的缺陷略大于伸展运动。准确性方面的相对缺陷显示出伸展运动比抓握运动更大的趋势,但这种差异未达到统计学显著性。相比之下,抓握运动中效率的相对缺陷比伸展运动更大,伸展效率接近正常表现范围。当考虑所有三个运动特征的数据时,急性偏瘫患者中使用远端节段进行有目的运动的能力并不明显比使用近端节段进行有目的运动的能力受到更严重的干扰。