单纤维肌电图在诊断腕管综合征中的表现和评价

目的 分析、评价单纤维肌电图(single fiber electromyography,SFEMG)在诊断腕管综合征中的表现和作用.方法 将临床确诊的14例腕管综合征患者(共20侧)根据常规电生理神经传导检测数据分为两组:患侧跨腕段SNCV(感觉神经传导)均减慢,但拇短展肌CMAP(复合肌肉动作电位)潜伏期正常者为腕管Ⅰ组(10侧),拇短展肌CMAP的潜伏期4.3ms者为腕管Ⅱ组(10侧).各组均行SFEMG检测,得到拇短展肌的纤维密度(fiber density,FD)和单纤维动作电位间间隔的连续差均值(mean of consecutive difference,MCD).10例(10侧)健康志愿者为对照组,同法测取FD、MCD值.结果 术前各组SFEbfG检测结果 :拇短展肌MCD平均值,腕管Ⅰ组为67.86μs,较对照组延长了27.47μs;腕管Ⅱ组为83.36μs,较对照组延长了42.97μs.拇短展肌FD平均值,腕管Ⅰ组较对照组增加了0.46,腕管Ⅱ组较对照组增加了0.60.腕管Ⅰ、Ⅱ组的MCD、FD明显高于对照组,Ⅱ组MCD又明显高于Ⅰ组,而Ⅰ组、Ⅱ组FD则无明显差异.结论 单纤维肌电图检测为腕部正中神经卡压,特别是早期卡压的诊断提供了一项新的更为直接的客观指标.

The resuits and value of single fiber electromyography in the diagnosis of CTS

Objective To analysis and evaluate the results of single fiber electromyography (SFEMG) in the diagnosis of carpal tunnel syndrorne (CIS). Methods According to results acquired by routine nerve conduction studies, 14 clinically diagnosed CTS patients (20 sides) were divided into 2 groups. In group Ⅰ(10 sides) although there was slowing of sensory nerve conduction velocity (SNCV) across the wrist, latency of the compound muscle action potential (CMAP) of abductor pollieis brevis (APB) was normal. In group Ⅱ(10 sides) in sdditiun to slow SNCV, CMAP latency of APB was more than 4.3 ms. Another 10 normal volunteers served as control. SFEMG was done to all the study subjects to obtain fiber density (FD) of the abductor pollicis brevis and mean of consecufive difference (MCD). Results Preoperative SPEMG showed that MCD of group Ⅰ was 67.86 μs on average, being 27.47 μs longer than that of the control group. MCD of group Ⅱ was 83.36μs on average, 42.97μs longer comparing to the control group. FD of abductor pollicis brevis was higher in both group Ⅰ and Ⅱ, with an increase of 0.46 and 0.60, respectively. MCD and FD in CTS patients were significanfly higher than those of normal control. MCD of group Ⅱ was significantly greater than MCD of group Ⅰ. However there was no significant difference in FD of both groups. Conclusion SFEMG provides more objective and direct evidence for the diagnose of Carpal tunnel syndrome, especially for cases in early stage.