Pease W S, Lee H H, Johnson E W
Department of Physical Medicine, Ohio State University, College of Medicine.
Electromyogr Clin Neurophysiol. 1990 Aug-Sep;30(5):299-302.
Reduced velocity of median nerve conduction in the forearm of patients with carpal tunnel syndrome (CTS) has been attributed to an artifact of the electrodiagnostic method rather than pathophysiologic changes in the forearm segment. Standard nerve conduction velocity (NCV) tests measure the forearm segment in combination with the distal latency and this may not represent an accurate assessment of conduction in the proximal portion of the nerve. A new technique of direct evaluation of the forearm median nerve was developed by the stimulation and recording of the forearm nerve action potential (FNAP) proximal to the wrist. The FNAP measurement was compared to the usual NCV in persons with CTS and control subjects. Forearm median nerve conduction velocities in the CTS group were significantly slower (p less than 0.05) than normal subjects using both FNAP and standard NCV techniques. The finding of decreased conduction speeds by the direct measurement of the forearm segment confirms that the reduced speeds derived from NCV are valid and suggests that retrograde degeneration of the nerve axons may result from entrapment in the carpal tunnel.
腕管综合征（CTS）患者前臂正中神经传导速度降低，一直被归因于电诊断方法的假象，而非前臂段的病理生理变化。标准神经传导速度（NCV）测试将前臂段与远端潜伏期结合测量，这可能无法准确评估神经近端的传导情况。通过刺激和记录腕部近端的前臂神经动作电位（FNAP），开发了一种直接评估前臂正中神经的新技术。将CTS患者和对照受试者的FNAP测量结果与常规NCV进行比较。使用FNAP和标准NCV技术时，CTS组的前臂正中神经传导速度均显著慢于正常受试者（p小于0.05）。通过直接测量前臂段发现传导速度降低，证实了从NCV得出的速度降低是有效的，并表明神经轴突的逆行性退变可能是由腕管受压所致。
