Clinical significance and associated factors of abnormal intraoperative neurophysiological monitoring signals in cervical degenerative disease surgery
10.3760/cma.j.cn121113-20250209-00120
- VernacularTitle:颈椎退行性疾病术中神经电生理监测异常变化的临床意义及诱发因素
- Author:
Jinhui SHI
1
;
Shanwen WEI
1
;
Fanqi KONG
1
;
Yuanchen ZHU
1
;
Jin QIAN
1
;
Hanfeng HU
1
;
Yang YANG
1
;
Chunju YANG
1
;
Huilin YANG
1
Author Information
1. 苏州大学附属第一医院骨科，苏州 215006
- Publication Type:Journal Article
- Keywords:
Cervical spondylosis;
Neurophysiological monitoring;
Evoked potentials;
Electromyography
- From:
Chinese Journal of Orthopaedics
2025;45(17):1119-1127
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinical significance and inducing factors of abnormal intraoperative neurophysiological monitoring (IONM) signals during surgery for cervical degenerative diseases.Methods:A retrospective analysis was performed on 586 patients who underwent cervical degenerative disease surgery with IONM at the Department of Orthopedics, The First Affiliated Hospital of Soochow University, from April 2015 to April 2024. Surgical approaches included 380 anterior spinal canal decompression and fusion procedures, 154 posterior spinal canal decompression and fusion procedures (including single-door laminoplasty, total laminectomy, and hemilaminectomy), and 52 combined anterior-posterior surgeries. The multimodal IONM protocol employed transcranial electrical stimulation motor evoked potentials (TES-MEP) and cortical somatosensory evoked potentials (CSEP), combined with electromyography (EMG). Bilateral deltoid muscles, thenar/hypothenar muscles and abductor hallucis muscles were monitored in all patients. Intraoperative MEP, SEP, and EMG results were recorded to analyze the causes of abnormal signals, intraoperative response strategies, and postoperative neurological function and outcomes. Fourfold table chi-square tests were used to analyze factors possibly associated with IONM alerts.Results:Among the 586 cervical surgeries, 17 cases (2.9%) exhibited abnormal IONM signals. These included 4 cases of anterior cervical discectomy and fusion (ACDF), 4 cases of anterior cervical corpectomy and fusion (ACCF), and 2 cases of combined anterior-posterior surgeries for cervical spondylotic myelopathy; and 5 posterior surgeries and 2 anterior ACCF procedures for ossification of the posterior longitudinal ligament (OPLL). The rate of abnormal IONM signals was significantly higher in patients with maximum spinal cord compression (MSCC)>60% (5.8%, 12/208) than in those with MSCC≤60% (χ 2=9.417, P=0.002); in patients with intraoperative hypotension during posterior surgery (mean arterial pressure reduction>20% from baseline, cumulative duration>20 min), the abnormal IONM rate was 22.2% (6/27), which was significantly higher than that in patients without intraoperative hypotension (χ 2=33.542, P<0.001); in patients who underwent calcified tissue removal during anterior surgery, the abnormal IONM rate was 9.3% (5/54), which was significantly higher than that in patients without calcified tissue removal (χ 2=13.162, P=0.003). Thus, MSCC>60%, intraoperative hypotension during posterior surgery, and calcified tissue removal during anterior surgery may be inducing factors for abnormal IONM signals. Among the 17 patients with monitoring abnormalities, 8 cases showed no significant improvement after corresponding intraoperative treatments, and 7 of these 8 cases experienced varying degrees of muscle strength decline and sensory numbness immediately after surgery; 9 cases showed partial or complete recovery of signals, among which 8 cases had no new-onset neurological impairment after surgery, and 1 case developed unilateral upper limb grip strength decline. IONM demonstrated a sensitivity of 0.8750 and specificity of 0.8889. Conclusions:Multimodal IONM can detect electrophysiological abnormalities of spinal cord nerve function during cervical degenerative disease surgery, providing real-time warning of potential nerve damage during the operation. The proportion of abnormal IONM signals is relatively high in cases with MSCC>60%, intraoperative hypotension during posterior cervical surgery, or calcified tissue removal during anterior cervical surgery.
