Calancie B, Ayyar D R, Eismont F J
Miami Project to Cure Paralysis, University of Miami School of Medicine, Florida.
Electromyogr Clin Neurophysiol. 1992 Sep;32(9):443-7.
In surgical cases during which spine nerve roots are at risk, we have found it useful to monitor EMG from the muscles supplied by those roots. Mechanical irritation of a root results in muscle activity, whose amplified signals can be broadcast over a loudspeaker, providing immediate feedback to the surgeon that the root is being irritated. We report here on a patient undergoing spinal canal decompression and fusion following a burst fracture of the L5 vertebral body sustained five days previously. EMG was continuously monitored from the tibialis anterior (TA) and medial gastrocnemius (MG) muscle groups bilaterally. During the period leading up to decompression, myokymic discharges from the left TA muscle were observed, whereas the other 3 muscles monitored did not show such activity. These semi-rhythmic and repetitive discharges from the left TA ceased immediately following surgical removal of a bone fragment compressing the left L5 nerve root. This indicates that the site of axonal irritation was the nerve root, and that myokymic discharges secondary to acute axonal compression can cease immediately upon nerve root decompression.
在脊柱神经根面临风险的外科手术病例中，我们发现监测由这些神经根所支配肌肉的肌电图（EMG）很有用。神经根受到机械刺激会导致肌肉活动，其放大后的信号可通过扬声器播放出来，从而为外科医生提供神经根受到刺激的即时反馈。我们在此报告一名患者，该患者在五天前发生L5椎体爆裂性骨折后接受了椎管减压和融合手术。双侧连续监测胫前肌（TA）和腓肠肌内侧头（MG）肌群的肌电图。在减压前的这段时间里，观察到左侧TA肌肉出现肌束震颤放电，而所监测的其他3块肌肉未显示出此类活动。在手术移除压迫左侧L5神经根的骨碎片后，左侧TA肌肉的这些半节律性和重复性放电立即停止。这表明轴突刺激的部位是神经根，并且急性轴突受压继发的肌束震颤放电在神经根减压后可立即停止。
