Laboratory of Neuromotor Physiology, Scientific Institute for Research, Hospitalization and Healthcare (IRCCS) Santa Lucia Foundation, Rome, Italy.
Department of Pediatric Neurorehabilitation, IRCCS Santa Lucia Foundation, Rome, Italy.
J Neurophysiol. 2020 Aug 1;124(2):574-590. doi: 10.1152/jn.00163.2020. Epub 2020 Jul 15.
We investigated how early injuries to developing brain affect the interaction of locomotor patterns with the voluntary action required by obstacle clearance. This task requires higher cognitive load and specific anticipatory sensorimotor integration than more automated steady-state gait. To this end, we compared the adaptive gait patterns during obstacle clearance in 40 children with cerebral palsy (CP) (24 diplegic, 16 hemiplegic, 2-12 yr) and 22 typically developing (TD) children (2-12 yr) by analyzing gait kinematics, joint moments during foot elevation, electromyographic (EMG) activity of 11 pairs of bilateral muscles, and muscle modules evaluated by factorization of the EMG signals. The results confirmed generally slower task performance, plus difficulty in motor planning and control in CP. Thus ~30% of diplegic children failed to perform the task. Children with CP demonstrated higher foot lift, smaller range of motion of distal segments, difficulties in properly activating the hamstring muscles at liftoff, and a modified hip strategy when elevating the trailing limb. Basic muscle modules were generally roughly similar to TD patterns, though they showed a limited adaptation. Thus a distinct activation burst in the adaptable muscle module timed to the voluntary task (liftoff) was less evident in CP. Children with CP also showed prolonged EMG burst durations. Impaired obstacle task performance may reflect impaired or less adaptable supraspinal and spinal control of gait when a locomotor task is superimposed with the voluntary movement. Neurorehabilitation of gait in CP may thus be beneficial by adding voluntary tasks such as obstacle clearance during gait performance. Previous studies mainly evaluated the neuromuscular pattern generation in cerebral palsy (CP) during unobstructed gait. Here we characterized impairments in the obstacle task performance associated with a limited adaptation of the task-relevant muscle module timed to the foot lift during obstacle crossing. Impaired task performance in children with CP may reflect basic developmental deficits in the adaptable control of gait when the locomotor task is superimposed with the voluntary movement.
我们研究了早期脑损伤如何影响运动模式与跨越障碍物所需的自主运动之间的相互作用。这项任务需要更高的认知负荷和特定的前瞻性感觉运动整合，而不是更自动化的稳态步态。为此，我们通过分析步态运动学、足部抬高时的关节力矩、11 对双侧肌肉的肌电图（EMG）活动以及通过 EMG 信号的因子分解评估的肌肉模块，比较了 40 名脑瘫（CP）儿童（24 名四肢瘫，16 名偏瘫，2-12 岁）和 22 名正常发育（TD）儿童（2-12 岁）在跨越障碍物时的适应性步态模式。结果证实，CP 儿童的总体表现较慢，运动计划和控制能力较差。因此，约 30%的四肢瘫儿童无法完成任务。CP 儿童表现出更高的抬脚高度、更小的远端节段运动范围、在抬脚时难以正确激活腘绳肌以及在提升随动肢体时改变髋关节策略。基本的肌肉模块通常与 TD 模式大致相似，但它们表现出有限的适应性。因此，在 CP 中，与自主任务（抬脚）时间匹配的适应性肌肉模块的明显激活爆发不太明显。CP 儿童还表现出 EMG 爆发持续时间延长。障碍物任务表现受损可能反映了在将运动任务叠加到自主运动时，对步态的上运动和脊髓控制受损或适应性较差。因此，在 CP 中，通过在步态表现期间添加障碍物清除等自主任务来进行步态神经康复可能是有益的。以前的研究主要评估了脑瘫（CP）在无障碍步态时的神经肌肉模式生成。在这里，我们描述了与跨越障碍物时与抬脚时间匹配的任务相关肌肉模块的适应性有限相关的障碍任务表现受损。CP 儿童的任务表现受损可能反映了在将运动任务叠加到自主运动时，对步态的适应性控制存在基本的发育缺陷。
