Preoperative electrophysiologic assessment of C5-innervated muscles in predicting C5 palsy after posterior cervical decompression

To investigate the feasibility of both needle electromyography (EMG) and proximal nerve conduction studies (NCS) in predicting C5 palsy after posterior cervical decompression. This study included 192 patients with myelopathy undergoing laminoplasty or laminectomy. Preoperatively, all accepted bilateral EMG detection NCS that consisted supramaximally stimulating Erb’s point recording compound muscle action potential (CMAP) from deltoid. In present study, 11 (11/192, 5.7%) developed unilateral operation, more showed abnormal spontaneous activity C5-innervated muscles compared to those without (8/11 vs. 16/181, p < 0.05). The sensitivity specificity postoperative were 72.7% 91.2%, respectively. Furthermore, there significant left-to-right differences deltoid CMAP amplitudes between (p 0.05), this measurement was also demonstrated be useful for distinguishing cases by receiver operating characteristic (ROC) curve analysis (cut-off value: 2.1 mV, sensitivity: 63.6%; specificity: 95.0%). addition, a series application these two measurements 63.6% 100.0%, findings support hypothesis pre-existing progressive root injury may risk factor Clinically, estimation provide additional information spinal surgery. Diagnostic: individual cross-sectional consistently applied reference standard blinding.