Dobkin B H, Harkema S, Requejo P, Edgerton V R
School of Medicine, University of California Los Angeles 90095-6975, USA.
J Neurol Rehabil. 1995;9(4):183-90.
Treadmill training with partial body weight support (BWS) is being advocated as a strategy to enhance walking in patients with spinal cord injury (SCI). Clinical reports have not examined the range of sensory inputs that might modulate electromyographic (EMG) output in the legs during training. During passive, manually assisted stepping on a treadmill with partial BWS, we found similar rhythmical EMG activity in the flexor and extensor muscles of the lower extremities in subjects who had chronic, complete thoracic spinal cord injuries and in subject who had incomplete lesions that resulted in minimal motor control and an inability to ambulate. The EMG bursts were temporally synchronized to specific phases of the step cycle, and their amplitudes and durations were modulated by varying the treadmill speed and the level of limb loading. Hip extension at the end of stance often induced involuntary hip flexion that initiated the swing phase. When the incomplete SCI subjects attempted volitional stepping, the EMG bursts in some muscles had a similar waveform but greater amplitude and duration compared to that observed during passive, assisted stepping. This suggests that, as in the model of the cat after a thoracic spinal transection, peripheral sensory inputs that are associated with rhythmical locomotion can enhance the output of lumbosacral neural circuits that contribute to step-like EMG activity, even in the absence of supraspinal descending influences. Attention should be given to optimizing the manipulation of sensory inputs during rehabilitation efforts with body weight supported treadmill training.
使用部分体重支持（BWS）的跑步机训练被提倡作为一种改善脊髓损伤（SCI）患者步行能力的策略。临床报告尚未研究在训练过程中可能调节腿部肌电图（EMG）输出的感觉输入范围。在部分BWS的跑步机上进行被动、手动辅助踏步时，我们发现慢性完全性胸段脊髓损伤患者以及不完全性损伤导致最小运动控制且无法行走的患者下肢屈肌和伸肌中存在类似的节律性EMG活动。EMG爆发在时间上与步周期的特定阶段同步，其幅度和持续时间通过改变跑步机速度和肢体负荷水平进行调节。站立末期的髋关节伸展常引发非自愿的髋关节屈曲，从而启动摆动阶段。当不完全性SCI患者尝试自主踏步时，与被动辅助踏步期间相比，一些肌肉中的EMG爆发具有相似的波形，但幅度和持续时间更大。这表明，如同胸段脊髓横断后的猫模型一样，与节律性运动相关的外周感觉输入可以增强腰骶神经回路的输出，这些回路有助于产生类似踏步的EMG活动，即使在没有脊髓上运动影响的情况下也是如此。在进行体重支持跑步机训练的康复过程中，应注意优化感觉输入的操作。
