Metzger Anthony J, Dromerick Alexander W, Schabowsky Christopher N, Holley Rahsaan J, Monroe Brian, Lum Peter S
Center for Applied Biomechanics and Rehabilitation Research, National Rehabilitation Hospital, Washington, DC, USA.
J Rehabil Res Dev. 2010;47(3):201-11. doi: 10.1682/jrrd.2009.06.0075.
The rate of upper-limb amputations is increasing, and the rejection rate of prosthetic devices remains high. People with upper-limb amputation do not fully incorporate prosthetic devices into their activities of daily living. By understanding the reaching behaviors of prosthesis users, researchers can alter prosthetic devices and develop training protocols to improve the acceptance of prosthetic limbs. By observing the reaching characteristics of the nondisabled arms of people with amputation, we can begin to understand how the brain alters its motor commands after amputation. We asked subjects to perform rapid reaching movements to two targets with and without visual feedback. Subjects performed the tasks with both their prosthetic and nondisabled arms. We calculated endpoint error, trajectory error, and variability and compared them with those of nondisabled control subjects. We found no significant abnormalities in the prosthetic limb. However, we found an abnormal leftward trajectory error (in right arms) in the nondisabled arm of prosthetic users in the vision condition. In the no-vision condition, the nondisabled arm displayed abnormal leftward endpoint errors and abnormally higher endpoint variability. In the vision condition, peak velocity was lower and movement duration was longer in both arms of subjects with amputation. These abnormalities may reflect the cortical reorganization associated with limb loss.
上肢截肢的发生率正在上升，而假肢装置的排斥率仍然很高。上肢截肢者并未将假肢装置充分融入其日常生活活动中。通过了解假肢使用者的伸手行为，研究人员可以改进假肢装置并制定训练方案，以提高对假肢的接受度。通过观察截肢者非残疾手臂的伸手特征，我们可以开始了解截肢后大脑如何改变其运动指令。我们要求受试者在有视觉反馈和无视觉反馈的情况下，对两个目标进行快速伸手动作。受试者用假肢手臂和非残疾手臂完成任务。我们计算了终点误差、轨迹误差和变异性，并将其与非残疾对照受试者的相应指标进行比较。我们发现假肢手臂没有明显异常。然而，我们发现在视觉条件下，假肢使用者非残疾手臂（右臂）存在异常的向左轨迹误差。在无视觉条件下，非残疾手臂表现出异常的向左终点误差和异常高的终点变异性。在视觉条件下，截肢受试者双臂的峰值速度较低，运动持续时间较长。这些异常可能反映了与肢体缺失相关的皮质重组。
