统计法运动单位数目估计技术的临床应用研究

目的研究统计法运动单位数目估计(MUNE)技术在下运动神经元轴索变性和脱髓鞘疾病诊断中的价值。方法共收集41例肌萎缩侧索硬化(ALS)、25例获得性脱髓鞘疾病和48名健康对照,对正中神经/拇短展肌采用统计法MUNE技术进行测定,分析比较运动单位数目、表面记录的运动单位电位(SMUP)平均波幅、最大SMUP波幅以及刺激反应功能曲线在3组研究对象之间的特点。结果在ALS、脱髓鞘疾病和健康对照组,数目加权的运动单位数目分别为49±20、109±38、118±12,平均SMUP波幅分别为(121±51)、(58±33)、(110±25)μV,最大SMUP波幅分别为(263±150)、(107±74)、(139±36)μV,复合肌肉动作电位分别为(5.8±2.8)、(6.5±4.6)、(13.1±2.8)mV。与健康对照组比较,ALS组运动单位数目明显下降(P<0.01)、最大SMUP波幅明显增高(P<0.01);与健康对照组和ALS组比较,脱髓鞘组平均SMUP波幅明显下降(P<0.01),而运动单位数目、最大SMUP波幅与健康对照组差异无统计学意义。ALS组刺激反应功能曲线明显不规则,最大采样区间明显增大。结论ALS患者运动单位数目降低,最大SMUP波幅增高,刺激反应功能曲线上的最大采样区间增大;脱髓鞘患者平均SMUP波幅明显下降。在某些情况下,根据上述特点,可以将统计法MUNE技术作为一种无创的方法,来协助鉴别周围神经脱髓鞘和轴索损害。     

统计法运动单位数目估计技术的可重复性研究

目的 对统计法运动单位数目估计技术的可重复性进行分析,为临床应用提供依据.方法 收集19例肌萎缩侧索硬化患者和27例正常对照者的临床资料,于同期对同一侧正中神经/拇短展肌进行两次统计法运动单位数目估计检测,计算其变化率,根据不同分析方法判断统计法运动单位数目估计技术的可重复性.结果 肌萎缩侧索硬化组受试者前后两次运动单位数目估计测值分别为(47.21±23.50)和(44.84±23.01),正常对照组受试者分别为(119.51±9.84)和(120.56±10.60),差异均无统计学意义(P＞0.05);两次测值之间均存在明显正相关关系(P＜0.05).肌萎缩侧索硬化组受试者运动单位数目估计测值的变化率P50(P25,P75)为9.52%(5.63%,25.00%),正常对照组受试者为5.00%(2.34%,9.40%),差异有统计学意义(Z=2.387,P=0.017),提示肌萎缩侧索硬化组受试者的可重复性低于正常对照组.肌萎缩侧索硬化组5例(5/19)患者运动单位数目估计测值的变化率＞25.00%,其正中神经远端复合肌肉动作电位波幅为1.90～3.20mV;14例(14/19)变化率≤25.00%,其正中神经远端复合肌肉动作电位波幅为3.80～12.40mV.结论 肌萎缩侧索硬化患者和正常对照者统计法运动单位数目估计检测均具有较好的可重复性,但是肌萎缩侧索硬化患者的可重复性低于正常对照者.建议在应用统计法运动单位数目估计,技术进行随访观察时,尽量选择复合肌肉动作电位波幅较高者进行检测.     

运动单位数目测定在神经源性疾病中的价值

目的：探讨运动单位数目测定（ＭＵＮＥ）对神经肌肉疾病的诊断价值。方法：应用ＶｉｋｉｎｇⅣ型肌电图仪中的“统计学方法”对８５例健康人和５６例神经源性病变患者的趾短伸肌和鱼际肌进行测定。记录和刺激电极均为表面电极。结果：对照组的结果显示可重复性好,≤６０岁时,运动单位数与年龄,性别与左右侧无关;〉６０岁时,ＭＵ数显著减少。     

糖尿病感觉神经病患者的运动单位数目估计

目的 通过运动单位数目估计技术检测糖尿病感觉神经病患者运动单位,以期评估其下运动神经功能状态.方法 纳入54例符合世界卫生组织糖尿病周围神经病国际协作研究诊断标准的糖尿病周围神经病(DPN)住院患者,并根据尺神经传导异常结果分组:感觉异常组(即仅有感觉传导异常而运动传导正常)33例,其中男20例,女13例;感觉运动异常组(即感觉传导和运动传导均异常)21例,其中男13例,女8例,并与42名健康人对照.应用Keypoint4肌电诱发电位仪,计数各组小鱼际肌运动单位数目,同时记录54例DPN患者入院后糖尿病病程和空腹血糖.结果 感觉异常组、感觉运动异常组和健康对照组的小鱼际肌运动单位数目分别为97.1±47.6、63.3±22.3、173.0±75.5(F=21.259,P=0.000);54例DPN患者小鱼际肌运动单位数目(84.0±42.8)与糖尿病病程(1个月至26年)呈负相关(r=0.414,P=0.002),与空腹血糖水平(5.0～20.4 mmol/L)无明显相关.结论 糖尿病感觉神经病存在着临床下运动神经损害,运动单位的丢失程度受糖尿病病程的影响.     

第九届全国肌电图与临床神经生理会议纪要

第九届全国肌电图与临床神经生理会议于2006年7月6—10日在风景优美的海滨城市大连召开。此次会议由中华医学会神经病学分会肌电图与神经电生理学组和中华神经科杂志编辑委员会共同策划承办。参会人员包括全国各地的神经科电生理专业的医生和技师约200余人。国内神经电生理专业的老专家汤晓芙、沈定国、康德碹、孙相如等教授均出席了会议。会议举行了隆重的开幕式，由此次大会主席崔丽英教授、原中华医学会中华神经病学会肌电图与神经电生理学组组长汤晓芙教授、中华神经科杂志编辑部主任包雅琳编审分别致贺词。在热烈隆重的气氛中，新一届的神经电生理学组成员向汤晓芙、康德碹和沈定国等教授颁发学组的荣誉奖章，感谢他们在中国肌电图和神经电生理学的奠定和发展中作出的卓越贡献。会议就肌电图的检查手段和方法学、运动神经元病的电生理研究、糖尿病的电生理研究、各种诱发电位在临床中的应用、脑电图的研究、事件相关电位的应用等方面作了广泛的交流，并安排了精彩的专题报告。     

运动单位数目测定的影响因素

目的：探讨运动单位数目测定（ＭＵＮＥ）的影响因素,方法：应用Ｎｉｃｏｌｅｔ的ＶｉｋｉｎｇＩＶ型肌电图仪中的“统计学方法”对８５例健康不的趾短伸肌、鱼于肌和小鲁际肌进行测定。记录和刺激电极均为表面电极。结果：结果显示,〈６０岁时,运动单位（ＭＵ）数与年龄、性别和左右侧无关;〉６０岁时,ＭＵ数显著减少,且小鱼际肌ＭＵ数目的减少程度显著小于鱼际肌和趾短伸肌,而后两者之间无显著差异。结论：ＭＵＮＥ值受年龄     

The utility of motor unit number estimation methods versus quantitative motor unit potential analysis in diagnosis of ALS

Objective

To compare the diagnostic utility of motor unit number estimation (MUNE) methods to motor unit potential (MUP) analysis in amyotrophic lateral sclerosis (ALS).

Motor unit number estimation in the quantitative assessment of severity and progression of motor unit loss in Hirayama disease

Objective

To investigate motor unit number estimation (MUNE) as a method to quantitatively evaluate severity and progression of motor unit loss in Hirayama disease (HD).

Determinants of mean motor unit size: Impact on estimates of motor unit number

The purpose of this study was to compare two fundamentally different methods of deriving the average surface-detected motor unit action potential (S-MUAP) size from which to calculate a motor unit number estimate (MUNE), namely: (1) the simple arithmetic average of S-MUAP parameter values; and (2) a computer-derived datapoint by datapoint average waveform which takes account of differences in S-MUAP shapes and durations. Multiple point stimulation was used to collect representative samples of between 11 and 20 S-MUAPs (mean 15 ± 2 SD) from the median-innervated thenar muscles of 20 healthy control subjects between 20 and 76 years of age (mean 48 ± 19 SD). The average S-MUAP size based on peak-to-peak amplitude, negative peak amplitude, and negative peak area measurements was calculated using the two different methods. The mean S-MUAP sizes based on the average waveform were significantly lower in all cases than those based on the simple average of S-MUAP parameter values. Differences tended to be greatest for MUNEs based on peak-to-peak amplitude (35%), less for negative peak amplitude (20%), and least for negative peak area (16%). © 1993 John Wiley & Sons, Inc.     

Electrophysiological diagnosis of motor neuron disease and pure motor neuropathy

Motor neuron disease (MND) is a group of disorders in which there is degeneration of upper and lower motor neurons to a variable degree. Amyotrophic lateral sclerosis is the most frequent form of the disease, presenting with both upper and lower motor neuron involvement. Frequently, especially in the early stages of the disease, only lower motor neuron signs are present. In these conditions, some pure motor neuropathies may resemble MND. The diagnosis is of importance because some of these motor neuropathies are “dysimmune” disorders and may respond to immune therapies. In such diseases the multifocal motor neuropathy with conduction block appears to be the more frequent. In MND and pure motor neuropathies, the electrophysiological examination is the most decisive test. In MND, it is of diagnostic importance. In addition, it is useful in the assessment of disease severity and progression, in the evaluation of therapeutic trials and in the understanding of etiopathogenesis of the disease. In pure motor neuropathies, the presence of conduction block leads to immune treatment with good response in more than 50% of the cases. Received: 20 August 1998 Accepted: 10 October 1998     

The firing rate of motor units in neuromuscular disorders

Summary The firing frequency and interval variability of motor units was studied in healthy controls and in patients suffering from peripheral neuromuscular disorders. In patients with myopathic disorders, the motor unit reached a higher firing frequency than in the controls during a slight muscle contraction although interval variability did not differ significantly from controls. In neurogenic lesions the firing rate also reached a higher level than in controls; in addition the interval variability was significantly increased. The firing characteristics of motor units may prove to be a valuable aid in the differential diagnosis of neuromuscular diseases.

---

Zusammenfassung Die Entladungsfrequenz und die Variationen zwischen den Intervallen motorischer Einheiten wurden sowohl bei Patienten, die an Störungen peripherer Neuromuskulatur leiden, als auch bei Normalfällen im Vergleich untersucht. Während einer leichten Muskelkontraktion wiesen die an myopathischen Störungen leidenden Patienten, verglichen mit den Normalfällen, eine höhere Entladungsfrequenz motorischer Einheiten auf, trotz der unbedeutenden Unterschiede in Intervallvariationen zwischen den Untersuchungsgruppen. Eine größere Steigerung der Entladungsrate wurde auch bei neurogenen Läsionen festgestellt, in diesem Zusammenhang hatten auch die Abweichungen zwischen den Intervallen beträchtlich zugenommen. Die Entladungscharakteristika motorischer Einheiten können einen wertvollen Beitrag zur Differentialdiagnostik bei neuromuskulären Störungen liefern.

     

Decreased motor unit number estimates in juvenile myoclonic epilepsy.

In this study, motor unit number estimate (MUNE) analysis with McComa's technique was used to detect any change in lower motor neuron count in juvenile myoclonic epilepsy (JME). The study included 10 JME patients, 8 idiopathic generalized epilepsy (IGE) patients, 7 patients with mesial temporal sclerosis (MTS), and 15 normal subjects. All the patients and normal subjects were subjected to MUNE analysis on the abductor pollicis brevis and tibialis anterior muscles, as well as needle electromyography and nerve conduction studies. Electromyographic and nerve conduction studies were normal in all groups. MUNEs in the JME group and were significantly lower than those of normal subjects (P < 0.001). MUNEs of IGE and MTS patients also tended to be lower than that of normal subjects with no significant difference from normal subjects. MUNEs of abductor pollicis brevis and tibialis anterior muscles were 114 +/- 24 and 90 +/- 15 for normal subjects, 59 +/- 18 and 50 +/- 23 for JME patients, 91 +/- 22 and 75 +/- 19 for IGE patients, and 84 +/- 42 and 80 +/- 29 for MTS patients respectively. It may be reasonable to suggest that a genetic origin is responsible for a tendency to contract epilepsy, and the disorganization of lower motor neurons may be shared in JME.     

Quantitative assessment of motor impairment and surgical outcome in Hirayama disease with proximal involvement using motor unit number index

ObjectiveTo assess the feasibility of motor unit number index (MUNIX) in quantitatively evaluating Hirayama disease (HD) with proximal involvement and to identify the effectiveness of anterior cervical fusion (ACF) in treating atypical HD with proximal involvement.MethodsThis study included 28 atypical HD patients with proximal involvement (proximal-distal vs. distal-proximal groups: 5 vs. 23) and 41 healthy controls. All patients underwent pre- and postoperative 1-year MUNIX tests on abductor pollicis brevis (APB), abductor digiti minimi (ADM), biceps brachii (BB) and deltoid (Del). The disabilities of arm, shoulder and hand (DASH) and Medical Research Council (MRC) scales were also performed in these patients before and one year after operation.ResultsPreoperatively, the patients in the distal-proximal group showed reduced compound muscle action potential (CMAP), decreased MUNIX and increased motor unit size index (MUSIX) in bilateral distal muscles and symptomatic-side proximal muscles (P < 0.05), and similar abnormalities were also observed in ADM, BB and Del on the symptomatic side in the proximal-distal groups (P < 0.05). Postoperative follow-up analysis identified increased MUNIX in the symptomatic-side proximal muscles with improved motor function in the proximal-distal groups (P < 0.05), and distal-proximal group patients showed an increase in both CMAP and MUSIX in the symptomatic-side proximal muscles (P < 0.05).ConclusionsMUNIX may serve as an available supplementary test to quantitatively evaluate the motor dysfunction and treatment outcome in HD with proximal involvement. ACF procedures can effectively treat these atypical HD patients, especially for those whose symptoms started in proximal muscles.     

Inter-rater reliability of motor unit number estimates and quantitative motor unit analysis in the tibialis anterior muscle

ObjectiveTo establish the inter-rater reliability of decomposition-based quantitative electromyography (DQEMG) derived motor unit number estimates (MUNEs) and quantitative motor unit (MU) analysis.MethodsUsing DQEMG, two examiners independently obtained a sample of needle and surface-detected motor unit potentials (MUPs) from the tibialis anterior muscle from 10 subjects. Coupled with a maximal M wave, surface-detected MUPs were used to derive a MUNE for each subject and each examiner. Additionally, size-related parameters of the individual MUs were obtained following quantitative MUP analysis.ResultsTest–retest MUNE values were similar with high reliability observed between examiners (ICC = 0.87). Additionally, MUNE variability from test–retest as quantified by a 95% confidence interval was relatively low ($\pm 28$ MUs). Lastly, quantitative data pertaining to MU size, complexity and firing rate were similar between examiners.ConclusionMUNEs and quantitative MU data can be obtained with high reliability by two independent examiners using DQEMG.SignificanceEstablishing the inter-rater reliability of MUNEs and quantitative MU analysis using DQEMG is central to the clinical applicability of the technique. In addition to assessing response to treatments over time, multiple clinicians may be involved in the longitudinal assessment of the MU pool of individuals with disorders of the central or peripheral nervous system.