体感诱发电位联合肌电图在颈椎手术中监护的价值探讨

The value of somatosensory evoked potential combined with EMG monitoring in cervical spine surgery

目的评估颈椎手术中采用体感诱发电位（somatosensory evoked potential，SEP）联合肌电图（electromyogram，EMG）电生理监护方案的敏感度和特异度。方法对2014年12月至2016年5月90例行术中电生理监护的颈椎病患者进行回顾性分析，男58例，女32例；年龄28-76岁，平均（52±20）岁。24例颈椎后纵韧带骨化症（ossification of posterior longitudinal ligament，OPLL）和42例脊髓型颈椎病行前路手术，24例颈椎OPLL行后路单开门手术。所有患者术中均采用双侧正中神经和胫神经SEP监护，联合双侧三角肌和肱二头肌EMG监护。对患者术前和术后3个月的神经功能采用日本骨科协会（Japanese Orthopaedic Association Scores，JOA）评分进行评价。记录患者术中的SEP和EMG监护结果，并分别计算SEP监护、EMG监护和SEP＋EMG联合监护的敏感度、特异度、假阳性率、假阴性率、阳性预测值、阴性预测值。结果90例患者中81例术后即刻JOA评分获得明显改善，余9例术后出现不同时间的神经功能恶化。4例颈椎OPLL和1例脊髓型颈椎病行前路手术患者术中出现一过性SEP报警，EMG未报警，术后其中1例患者出现一过性单侧脊髓型神经功能恶化，术前JOA评分13分，术后即刻8分，术后3个月恢复至14分。8例患者（4例颈椎OPLL行前路手术、2例颈椎OPLL行后路手术、2例脊髓型颈椎病行前路手术）术中出现EMG报警，SEP未报警，其中4例（2例颈椎OPLL行后路手术、2例脊髓型颈椎病行前路手术）术后出现一过性C，神经根麻痹，术前JOA评分14-15分，术后即刻10-11分，术后3个月13-15分。SEP监护的敏感度、特异度、假阳性率、假阴性率、阳性预测值、阴性预测值分别为55．5％、100％、0、44．4％、100％、95．3％，EMG分别为44．4％、95．1％、4．9％、55．5％、50．0％、93．9％，SEP＋EMG联合监护分别为100％、95．1％、4．9％、0、69．2％、100％。结论正中神经、胫神经SEP联合三角肌、肱二头肌EMG监护在颈椎手术中可以达到有效的监护效果，提高了监护的敏感性，对术后脊髓神经功能恶化起到有效的预防作用，特别是c，神经根麻痹。

Objective To analyze the sensitivity and specificity of SEP and EMG combined monitoring for cervical surgery. Methods Data of 90 patients （58 males and 32 females, age 28-76 years, averaged 52_＋20 years） who bad undergone neurological monitoring during cervical spine surgery from Dec. 2014 to May 2016 （24 cervical OPLL cases and 42 cervical myelopathy cases through anterior approach, 24 cervical OPLL through posterior approach） were retrospectively analyzed. SEP monitoring of bilateral median nerves and tibial nerves, combined with EMG monitoring of bilateral deltoid and biceps muscles were performed for all the patients. The neurological status was evaluated by JOA score before the surgery and 3 months after the surgery. The sensitivity, specificity, false positive rate, false negative rate, positive predictive value and negative predictive value of SEP, EMG and EMG＋SEP techniques were calculated. Results The JOA score improved after the surgery in 81 of 90 patients. In 4 cases of anterior cervical decompression and fixation for cervical OPLL and 1 case of cervical spondylotic myelopathy, temporary abnormal change was detected in SEP monitoring. In one patient, temporary single side neurological deterioration was detected, whose JOA was 13 preoperatively, which decreased to 8 instantly after surgery and increased to 14 at 3-month follow-up. There were 8 patients （4 cases of OPLL with anterior approach, 2 cases of OPLL with posterior approach, 2 cases of cervical spondylotic myelopathy with anterior approach） had abnormal EMG change without SEP abnormal change during the surgery. 4 patients had temporary C5 nerve palsy after surgery. The JOA was 14-15 preoperatively, which declined to 10-11 instantly after surgery and increased to 13-15 at 3-month follow-up. The sensitivity, specificity, false positive rate, false negative rate, positive predictive value and negative predictive value was 55.5%, 100%, 0, 44.4%, 100%, and 95.3% for SEP, while 44.4%, 95.1%, 4.9%, 55.5%, 50% and 93.9% for EMG and 100%, 95.1%, 4.9%, 0%, 69.2% and 100% for EMG＋SEP. Conclusion SEP combined with EMG monitoring increased the sensitivity in neurological monitoring for cervical spine surgery, which can prevent severe neurological deterioration, especially C5 nerve palsy.