Malone Ailish, Meldrum Dara, Gleeson John, Bolger Ciaran
Gait Analysis Laboratory, Central Remedial Clinic, Clontarf, Dublin 3, Ireland,
Eur Spine J. 2013 Nov;22(11):2538-44. doi: 10.1007/s00586-013-2928-9. Epub 2013 Aug 2.
Gait impairment in cervical spondylotic myelopathy (CSM) is characterised by a number of kinematic and kinetic abnormalities. Surface electromyography (EMG) can evaluate the contributions of individual muscles to a movement pattern and provide insight into the underlying impairments that characterise an abnormal gait. This study aimed to analyse EMG signals from major lower limb muscles in people with CSM and healthy controls during gait.
Sixteen people with radiologically confirmed CSM and 16 matched healthy controls participated in gait analysis. Surface EMG was recorded during walking from four lower limb muscles bilaterally. The timing of muscle activation, relative amplitudes of each burst of activity and baseline activation during gait, and the muscles' responses to lengthening as a measure of spasticity were compared using previously validated methods of EMG analysis.
Compared to healthy controls, people with CSM had prolonged duration of activation of biceps femoris (12.5% longer) and tibialis anterior (12.4%), prolonged co-activation of rectus femoris and biceps femoris (5.14%), and impaired scaling of the amplitude of rectus femoris and biceps femoris. Muscle activation in response to lengthening was similar between groups.
The results provide evidence for paresis as a contributory factor to gait impairment in CSM, indicated by impaired amplitude and the need for proximal co-activation to compensate for lack of distal power generation. Poor proprioception may have contributed to prolonged activation of tibialis anterior. Analysis of muscle responses to lengthening suggested that spasticity was not an important contributor. These findings have implications for the assessment and rehabilitation of gait impairment in CSM.
脊髓型颈椎病（CSM）患者的步态障碍表现为多种运动学和动力学异常。表面肌电图（EMG）可以评估个体肌肉对运动模式的贡献，并深入了解导致异常步态的潜在损伤。本研究旨在分析CSM患者和健康对照者在步态过程中主要下肢肌肉的肌电图信号。
16例经影像学确诊的CSM患者和16例匹配的健康对照者参与了步态分析。在行走过程中双侧记录来自四块下肢肌肉的表面肌电图。使用先前验证的肌电图分析方法，比较了肌肉激活的时间、每次活动爆发的相对幅度以及步态期间的基线激活，以及肌肉对延长的反应作为痉挛的一种测量指标。
与健康对照者相比，CSM患者股二头肌（延长12.5%）和胫骨前肌（延长12.4%）的激活持续时间延长，股直肌和股二头肌的共同激活延长（5.14%），股直肌和股二头肌的幅度缩放受损。两组之间对延长的肌肉激活反应相似。
结果为轻瘫是CSM患者步态障碍的一个促成因素提供了证据，表现为幅度受损以及需要近端共同激活以补偿远端动力产生不足。本体感觉差可能导致胫骨前肌激活时间延长。对肌肉对延长反应的分析表明，痉挛不是一个重要因素。这些发现对CSM患者步态障碍的评估和康复具有重要意义。
