Coscia Martina, Monaco Vito, Martelloni Chiara, Rossi Bruno, Chisari Carmelo, Micera Silvestro
Translational Neural Engineering Laboratory, Center for Neuroprosthetics and School of Engineering, École Polytechnique Fédérale de Lausanne, BM 3210, Station 17, 1015, Lausanne, Switzerland.
Neural Engineering Area, The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy.
J Neuroeng Rehabil. 2015 Apr 18;12:39. doi: 10.1186/s12984-015-0031-7.
Previous studies have shown that a cerebrovascular accident disrupts the coordinated control of leg muscles during locomotion inducing asymmetric gait patterns. However, the ability of muscle synergies and spinal maps to reflect the redistribution of the workload between legs after the trauma has not been investigated so far.
To investigate this issue, twelve post-stroke and ten healthy participants were asked to walk on a treadmill at controlled speeds (0.5, 0.7, 0.9, 1.1 km/h), while the EMG activity of twelve leg muscles was recorded on both legs. The synergies underlying muscle activation and the estimated motoneuronal activity in the lumbosacral enlargement (L2-S2) were computed and compared between groups.
Results showed that muscle synergies in the unaffected limb were significantly more comparable to those of the healthy control group than the ones in the affected side. Spinal maps were dissimilar between the affected and unaffected sides highlighting a significant shift of the foci of the activity toward the upper levels of the spinal cord in the unaffected leg.
Muscle synergies and spinal maps reflect the asymmetry as a motor deficit after stroke. However, further investigations are required to support or reject the hypothesis that the altered muscular organization highlighted by muscle synergies and spinal maps may be due to the concomitant contribution of the altered information coming from the upper part of the CNS, as resulting from the stroke, and to the abnormal sensory feedback due to the neuromuscular adaptation of the patients.
先前的研究表明，脑血管意外会破坏运动过程中腿部肌肉的协调控制，导致不对称步态模式。然而，迄今为止，尚未研究肌肉协同作用和脊髓图谱反映创伤后双腿间工作量重新分配的能力。
为研究此问题，12名中风后患者和10名健康参与者被要求在跑步机上以可控速度（0.5、0.7、0.9、1.1千米/小时）行走，同时记录双腿12块腿部肌肉的肌电图活动。计算并比较两组之间肌肉激活的潜在协同作用以及腰骶膨大（L2 - S2）中估计的运动神经元活动。
结果显示，与患侧相比，未受影响肢体的肌肉协同作用与健康对照组的协同作用更具可比性。患侧和未受影响侧的脊髓图谱不同，突出显示未受影响腿部活动焦点显著向上移至脊髓更高水平。
肌肉协同作用和脊髓图谱反映了中风后作为运动缺陷的不对称性。然而，需要进一步研究来支持或否定这一假设，即肌肉协同作用和脊髓图谱突出显示的肌肉组织改变可能是由于中风导致的来自中枢神经系统上部的信息改变以及患者神经肌肉适应引起的异常感觉反馈共同作用的结果。
