Hodapp Maike, Vry Julia, Mall Volker, Faist Michael
Department of Neurology and Clinical Neurophysiology, University Hospital Freiburg, Freiburg, Germany.
Brain. 2009 Jan;132(Pt 1):37-44. doi: 10.1093/brain/awn287. Epub 2008 Nov 3.
In healthy children, short latency leg muscle reflexes are profoundly modulated throughout the step cycle in a functionally meaningful way and contribute to the electromyographic (EMG) pattern observed during gait. With maturation of the corticospinal tract, the reflex amplitudes are depressed via supraspinal inhibitory mechanisms. In the soleus muscle the rhythmic part of the modulation pattern is present in children with cerebral palsy (CP), but the development of tonic depression with increasing age, as seen in healthy children, is disturbed. Treadmill training clinically improves the walking pattern in children with CP. Presuming that short latency reflexes contribute significantly to the walking pattern, a change in the modulation may occur after training. The aim of this study was to assess whether treadmill training also improves the soleus reflex modulation during gait in children with CP. Seven children with CP underwent brief treadmill training for 10 min a day over 10 consecutive days; all of them were functional walkers. Soleus Hoffmann (H-) reflexes were investigated during walking on a treadmill before the first, and one day after the last, training session. Treadmill training led to a considerable clinical improvement in gait velocity. After 10 days of training, soleus H-reflexes during gait were almost completely depressed during the swing phase. The complete suppression of the soleus H-reflex during the swing phase, which is also exhibited by healthy subjects, could reflect an improvement towards a functionally more useful pattern. In conclusion, treadmill training can induce changes in the modulation of short latency reflexes during gait.
在健康儿童中，短潜伏期腿部肌肉反射在整个步周期中以功能上有意义的方式受到深刻调节，并有助于在步态期间观察到的肌电图（EMG）模式。随着皮质脊髓束的成熟，反射幅度通过脊髓上抑制机制而降低。在比目鱼肌中，调制模式的节律部分在脑瘫（CP）儿童中存在，但如在健康儿童中所见，随着年龄增长的强直抑制的发展受到干扰。跑步机训练在临床上改善了CP儿童的步行模式。假定短潜伏期反射对步行模式有显著贡献，训练后调制可能会发生变化。本研究的目的是评估跑步机训练是否也能改善CP儿童步态期间的比目鱼肌反射调制。七名CP儿童连续10天每天在跑步机上进行10分钟的简短训练；他们都是功能性步行者。在第一次训练前和最后一次训练后一天，在跑步机上行走期间对比目鱼肌霍夫曼（H-）反射进行了研究。跑步机训练导致步态速度有显著的临床改善。训练10天后，步态期间比目鱼肌H反射在摆动期几乎完全被抑制。摆动期比目鱼肌H反射的完全抑制，这在健康受试者中也有表现，可能反映了向功能上更有用模式的改善。总之，跑步机训练可引起步态期间短潜伏期反射调制的变化。
