肌电图对多节段腰椎退行性疾病责任节段定位的诊断价值

Diagnostical value of electromyography in identifying responsible segments of multi-segmental lumbar degenerative diseases

中文关键词:  多节段腰椎退行性疾病  责任节段  肌电图

英文关键词:Multi-segmental lumbar degenerative diseases  Responsibility segment  Electromyography

中文摘要:

  【摘要】 目的：评估肌电图（electromyography，EMG）对多节段腰椎退行性疾病责任节段定位的诊断价值。方法：2007年1月~2015年1月收治多节段腰椎退行性疾病手术患者342例，男174例，女168例；平均年龄69.2岁，其中腰椎管狭窄症180例，腰椎管狭窄症合并腰椎间盘突出症95例，腰椎管狭窄症合并腰椎滑脱症55例，腰椎管狭窄症合并腰椎退行性侧凸12例。根据症状、体征和影像学检查确定责任节段224例，行神经根阻滞术确定责任节段118例。行单节段减压手术95例，双节段减压手术212例，3节段减压手术35例。术前对患者下肢运动神经和感觉神经进行神经传导检测，对下肢肌肉和腰骶部椎旁肌进行针电极EMG检测，对比目鱼肌进行H反射检测。所检测肌肉的针电极EMG出现失神经电位即纤颤电位、正锐波及复合重复放电（complex repetitive discharge，CRD）时，提示有神经损害；神经传导检测中运动神经传导速度（motor nerve conduction velocity，MCV）、感觉神经传导速度（sensory nerve conduction velocity，SCV）的异常标准：MCV＜40m/s，SCV＜39m/s；患侧H反射消失或双侧潜伏期差值＞1.5ms，提示存在S1神经根病变损害可能。EMG检测的灵敏度=EMG检测结果阳性与手术减压吻合的节段数/EMG检测所有节段中手术减压的节段总数，特异性=EMG检测结果阴性与未手术减压吻合的节段数/EMG检测所有节段中未手术减压的节段总数。结果：针电极EMG部分，正锐波和纤颤电位判定责任节段的灵敏度为72.5%，特异性为87.2%；CRD判定责任节段的灵敏度为8.7%，特异性为100%；宽大和多相的运动单位电位（motor unit potential，MUP）判定责任节段的灵敏度为92.2%，特异性为18.2%。神经传导检测部分，342例患者中，89例患者胫神经、101例患者腓总神经的肌肉复合动作电位（compound muscle action potential，CMAP）幅值降低，其中45例患者（病程＞3年）在趾短伸肌记录不到CMAP，但在胫前肌可记录到低幅值、速度正常的CMAP；所有患者胫神经、腓总神经运动传导速度正常，腓浅神经和腓肠神经的感觉传导正常。217例患者H反射消失，54例患者H反射潜伏期较健侧延长1.5ms。结论：CRD、正锐波和纤颤电位对诊断多节段腰椎退行性疾病责任节段的灵敏度和特异性较高，而MUP对责任节段的诊断价值较小。

英文摘要:

  【Abstract】 Objectives: To explore the value of electromyography(EMG) in diagnosing responsible segments of multi-segmental lumbar degenerative diseases. Methods: A total of 342 patients(male 174, female 168; average age, 69.2) with multi-segmental lumbar degenerative diseases were enrolled in this study from January 2007 to January 2015. 180 patients had lumbar spinal stenoses, 95 with lumbar spinal stenosis with disc herniation, 55 with lumbar spondylolisthesis and 12 with degenarative scoliosis. The responsible segments in 224 patients were confirmed according to the symptoms, signs and imageological examination, and 118 were diagnosed by preoperational subarachnoid root block. 95 patients underwent single-segment surgery, 212 patients had double-segment surgery, and 35 had three-segment fixation. The nerve conduction velocity of lower limb motor nerve and sensory nerve were performed. Lower limb muscle and paraspinal muscle in lumbosacral region were detected by the electromyography of needle pole. And H reflex was examined in soleus muscle. The muscles detected by needle EMG appeared the denevated potentials, that were, fibrillation potentials, positive sharp waves and compound repetitive discharge(CRD), suggesting the nerve injury. The abnormal standards of motor nerve conduction velocity(MCV) and sensory nerve conduction velocity(SCV) were detected in the nerve conduction studies(NCS): MCV<40m/s, SCV<39m/s. The patients with affected H reflex disappearing or bilateral latency difference more than 1.5ms, suggesting that S1 nerve root might be damaged. Electromyography detection sensitivity=the number of segments positive in electromyography test and surgical decompression anastomosis/total number of segments undergoing decompression in electromyography detection; the specificity=the number of segments negative in electromyography test/all segments without decompression. Results: Needle electromyography showed that the sensitivity and specificity of the responsible segments were 72.5% and 87.2%, respectively. The complex repetitive discharges(CRD) showed a sensitivity of 8.7% and a specificity of 100% in the responsible segments. The sensitivity and specificity of motor unit potential(MUP) turned out to be 92.2% and 18.2%. Nerve conduction detection showed decreased compound muscle action potential(CMAP) in tibial nerves of 89 patients and common peroneal nerves of 101 patients. In those patients, CMAP of extensor digitorum could not be detected in 45 patients whose disease courses were longer than 3 years, however, CMAP with low amplitude and normal speed of tibialis anterior in those patients could be observed. In all of the patients, the motor conduction velocities of common tibial nerves and common peroneal nerves as well as the sensory conductions of superficial peroneal nerves and sural nerves were normal. H reflexes disappeared in 217 patients, and the latencies of H reflex were prolonged 1.5ms in 54 patients. Conclusions: This prospective study demonstrates the positive and sharp waves and fibrillation potentials have a higher sensitivity and specificity in analyzing the responsible segment of multilevel lumbar degenerative disease. However, it is of less value of MUP in defining responsible segment.