Abstract: Objective To investigate the method of evaluating the severity of cervical spondylotic radiculopathy( CSR)and effects of the operation according to the results of electromyogram ( EMG). Methods Sixty patients with CSR undergoing anterior cervical decompression and fusion,were divided into three groups according to the results of EMG:mildly abnormal group ( 16 patients ), moderately abnormal group(19 patients)and severely abnormal group(25 patients). The patients′neck disability index( NDI)before surgery and 6 months after surgery were recorded. The postoperative NDI improvement rates of three groups were compared. Results The postoperative NDI scores of mildly abnormal group returned from moderate dysfunction to mild dysfunction. The postoperative NDI scores of moderately abnormal group returned from moderate dysfunction to mild dysfunction. The postoperative NDI scores of severely abnormal group returned from severe dysfunction to moderate dysfunction. Compared with mildly abnormal group ,the postoperative NDI improvement rates of moderately abnormal group and severely abnormal group were statistically significant( P ﹤0 . 05 ). Compared with moderately abnormal group,the postoperative NDI improvement rates of severely abnormal group were statistically significant ( P ﹤0 . 05 ). Conclusion Motor unit potentials with increased duration and amplitude in EMG tests accompanied by normal axillary nerve conduction velocity are the best electrophysiological indications for surgical treatment of CSR.

Key words: cervical spondylotic radiculopathy, electromyogram, surgical operation