Kamgar P, Agarwal A, Chao T, Askari S, Tan M, Honor R, Won Deborah S
Electrical and Computer Engineering Department, California State University - Los Angeles, Los Angeles, CA 90032, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2012;2012:1864-7. doi: 10.1109/EMBC.2012.6346315.
Applying neuromuscular electrical stimulation (NMES) during treadmill training (TT) has been shown to improve functional outcomes, such as gait speed and walking distance, in spinal cord injury (SCI) patients. However, ways to improve this combined NMES+TT therapy have not been investigated. We have developed NMES system for a rodent model of SCI to investigate whether and how more precisely timing the stimulation to robotically assisted hindlimb position might achieve rehabilitation of independent stepping after SCI. In our therapy (NMES+RTT), rodent ankle flexor muscles are stimulated while the hindlimbs are robotically driven through pre-programmed trajectories during treadmill training. The objectives of the work presented here were to quantify changes in step trajectory resulting from our combined NMES+RTT therapy and compare those effects with those induced by robotic treadmill training (RTT) alone. Animals were spinally contused to model severe SCI, and either received 2 weeks of NMES+RTT followed by 2 weeks of RTT (n=6) or 2 weeks of RTT followed by 2 weeks of NMES+RTT (n=7). Changes in step trajectories after training were analyzed. According to a deviation measure we developed, the step trajectories improved after either NMES+RTT or RTT training but more closely matched the desired pre-programmed trajectories after NMES+RTT than after RTT only. The step trajectories are also more consistent, as indicated by a coefficient of variation measure, after training and more so after NMES+RTT than after RTT only. These preliminary results from our NMES+RTT vs. RTT study are consistent with the hypothesis that appropriately timing NMES with hindlimb movements during stepping is an effective therapy for restoring the ability to step after spinal cord injury.
在脊髓损伤（SCI）患者的跑步机训练（TT）过程中应用神经肌肉电刺激（NMES）已被证明可改善功能结果，如步态速度和步行距离。然而，尚未对改善这种NMES + TT联合疗法的方法进行研究。我们为SCI啮齿动物模型开发了NMES系统，以研究在机器人辅助后肢位置时更精确地安排刺激时间是否以及如何能够实现SCI后独立行走的康复。在我们的治疗方法（NMES + RTT）中，在跑步机训练期间，当后肢通过预编程轨迹进行机器人驱动时，对啮齿动物的踝屈肌进行刺激。本文介绍的工作目标是量化我们的NMES + RTT联合疗法导致的步行动轨迹变化，并将这些效果与单独的机器人跑步机训练（RTT）所产生的效果进行比较。对动物进行脊髓挫伤以模拟严重的SCI，一组动物接受2周的NMES + RTT治疗，随后进行2周的RTT（n = 6），另一组接受2周的RTT，随后进行2周的NMES + RTT（n = 7）。分析训练后步行动轨迹的变化。根据我们开发的偏差测量方法，NMES + RTT或RTT训练后步行动轨迹均有所改善，但与仅进行RTT相比，NMES + RTT训练后的步行动轨迹更接近所需的预编程轨迹。步行动轨迹也更一致，这通过变异系数测量表明，训练后更一致，且NMES + RTT训练后比仅进行RTT时更一致。我们的NMES + RTT与RTT研究的这些初步结果与以下假设一致，即在步行过程中使NMES与后肢运动适当同步是恢复脊髓损伤后行走能力的有效疗法。
