H反射在腰腿痛患者中的应用

目的：探讨H反射在腰腿痛患者中的应用价值。方法：对象为腰腿痛患者113例,女性38例,男性75例;年龄18－62岁;病程2周－20年。嘱患者安静放松。室温26－28℃。针电极记录。记录电极插入腓肠肌内侧头或外侧头肌腹,表面电极刺激Guo部胫神经,逐渐增加电流刺激强度,直至引出最大波幅H波至M波开始出现为止,并且进行双下肢自身对照。结果：健侧／患侧H反射潜伏期平均值分别为：腓肠肌内侧头28.75ms/30.41ms;外侧头28.65ms/30.09ms。两侧之间的差异有显著性,同侧之间均无差异。健肢H反射与年龄、身高、性别均呈正相关,同侧H反射潜伏期之间高度相关。回归方程分别为：H反射（内侧头）＝4.98 0.04年龄（岁） 0.13身高（cm);H反射（外侧头）=6.78 0.06年龄 0.11身高（cm)。H反射潜伏期的异常与下肢痛、直腿抬高、跟腱反射相关,与腰痛、椎旁压痛关系不大。结论：H反射潜伏期与年龄、身高和性别相关。运用所得方程,临床医生可通过患者的年龄和所测身高来预测H反射潜伏期正常值。H反射潜伏期可用于判断腰腿痛患者腰骶神经损害的部位及程度。     

肢体近端肌肉磁刺激运动诱发电位正常值及临床应用

目的；对１００名健康志愿者按年龄，性别分组进行肢体近端肌肉记录的磁刺激运动诱发电位（ＭＥＰ）的测定。结果：ＭＥＰ潜伏期呈正态分布，最为稳定，变异小，重复性好，其中周围潜伏期与年龄，身高相关，与性别不相关；中枢运动传导时间与年龄，性别，身高均不相关，ＭＥＰ波幅呈偏态分布，变异较大；ＭＥＰ波宽呈正态分布，变异相对较大，结论：肢体近端肌肉记录的ＭＥＰ正常值的建立为临床提供了另一客观标准。     

磁刺激拇短展肌体感诱发电位的研究

磁刺激34名健康成人拇短肌肌腹,分别在体感传导通路的各个水平(Erb's点,第7颈椎棘突及对侧原发感觉皮眉)记录诱发电位,并与电刺激正中神经进行比较,结果发现除P_9波幅和中枢传导时间磁、电刺激间有显著性差异外,其它峰-峰波幅、峰间期两者均无明显差异;两者的N_(20)峰潜伏时均与身高明显相关。研究表明,磁刺激肌肉体感诱发电位可为定量评定肌肉传入纤维功能提供一简单可行而无损伤的方法;其机制可能是通过收缩肌肉、间接兴奋肌肉感受器和Ia传入纤维;其P_9、P_(1a)的神经发生源可能与电刺激相同,而皮层早成分则有待进一步研究。     

肌电图与神经传导速度对Graves病患者神经肌肉受损的评估

目的：应用肌电图和神经传导速度检查探讨Graves病神经肌肉受损的临床诊断意义。方法：于2000-05／2003-12选择汕头大学医学院第一附属医院内分泌专科门诊的Graves病患者46例为研究对象，行肌电图和神经传导速度检查；正常对照组31例为健康志愿者，31例行肌电图检查，30例行神经传导速度检查。肌电图检测：用同心圆针电极观察三角肌、股四头肌自发电位及募集形式，记录及分析小力收缩时每块肌肉20个运动单位电位平均时限及去多相波平均时限、波幅和多相波百分比。神经传导速度检测：用表面电极分别在腕部刺激正中神经和内踝胫后神经，于外展拇短肌及拇展肌用表面电极记录正中神经和胫后神经运动末端潜伏期和复合肌肉动作电位。用指环电极分别刺激拇指、中指和趾1，用表面电极于腕部及内踝记录测定感觉神经传导速度及波幅，包括正中神经（拇指-腕，中指-腕）和胫后神经（趾1-内踝）。并用超强电刺激在正中神经腕部及胫后神经踝部检测F波潜伏斯及出现率。结果：纳入受试对象77例，均进入结果分析。①Graves病组患者肌电图示小力收缩后时限缩短、波幅降低，大力收缩后其峰波幅降低。Graves病组胫后感觉神经复合肌肉动作电位波幅与正常对照组比较降低；正中感觉神经拇指-腕复合肌肉动作电位波幅降低；正中神经中指-腕感觉神经传导速度减慢；Graves病组正中神经F波潜伏期延长和异常出现率增加。键）416例Graves病患者有神经肌肉临床症状26例（56％），肌电图异常39例（85％）；神经传导速度异常41例（89％）；以肌电图异常判断神经传导速度异常敏感性为83％，特异性为87％；以神经传导速度异常判断肌电图异常敏感性为87％。特异性为83％。结论：两种方法对Graves病神经肌肉损伤诊断敏感性高于临床症状，对慢性甲状腺功能亢进性肌病诊断异常率、敏感性和特异性相近；肌电图主要对肌源性损害敏感，神经传导速度主要对神经源性损害敏感，具互补性。     

三叉神经-颈反射对运动神经元病球部损害的诊断价值

背景：运动神经元病的最早及好发部位为颈膨大，随病情发展，最早累及邻近的上部颈段及延髓区，三叉神经-颈反射受累较早。 目的：建立三叉神经-颈反射的肌电检测方法，分析三叉神经-颈反射对运动神经元病球部损害的诊断价值。 设计：病例-对照观察。 单位：北京大学第三医院神经内科电生理检查室。 对象：北京大学第三医院2002／2005就诊的运动神经元病患者主要为肌萎缩性侧索硬化症30例及健康志愿者70例。运动神经元病患者符合西班牙EI Escorial会议诊断标准。 方法：受检测者取仰卧位，头部轻度抬高。使胸锁乳突肌轻度收缩。刺激-侧眶下神经，于双侧胸锁乳突肌记录峰潜伏期和波幅。所用检测仪器为Keypoint肌电图仪。所用电极均为Ag／Agcl表面电极。 主要观察指标：正／负波潜伏期（P20／N30），波幅比率的平方根，即A值。 结果：刺激对照者一侧的眶下神经，可于双侧胸锁乳突肌引出正／负波。运动神经元病组7例正常（23．3％），8例未引出（26．7％），11例潜伏期延长（36．7％），4例双侧反射超常不对称（13．3％）。运动神经元病组三叉神经-颈反射正波／负波的峰潜伏期（P20／N30）明显高于正常对照组．差异有显著性。波幅比的平方根（峰值与刺激前波幅比值的平方根即A值）明显低于正常对照组，差异有显著性。 结论：三叉神经-颈反射能够可靠测定，可作为颈-球区病变的一种辅助检查手段，有助于运动神经元病的早期诊断。     

比目鱼肌按摩对内侧腓肠肌H反射的抑制效应

<正> Clin Neurophysiol.-1998,38.-81～86 按摩腓肠肌群时,同侧比目鱼肌的H反射峰-峰波幅降低,且持续时间与按摩时间一致,本研究旨在确定H反射波幅降低是否因按摩降低了运动神经元的兴奋性所致。 受试者为13例健康人,男4例,女9例,年龄21～32岁。俯卧,头右转,右膝屈17°,踝背屈15°。刺激电极阴极置于膑骨上大腿部,阳极置于内侧腓肠肌(MG)神经:一对Beckman微型记录电极置于     

利用H反射增强斜率评估比目鱼肌运动神经元池的兴奋性

<正> 利用H反射评定运动神经元(MN)池的兴奋性通常用三个指标:H反射的最大波幅(H_(最大)/M反应的最大波幅(M_(最大));H反射的阈值(H_(阈))/M反应的阈值(M_(阈));H反射恢复曲线。 作者使受试者在固定坐姿下进行重复的H反射测定,刺激方波宽0.5ms,频率0.3Hz。自H反射阈下开始刺激,每次增加0.5mA,直至引起最大M波。同一强度给予7个脉冲,求取7个H波或M波     

H反射在脑卒中后上肢偏瘫患者中的特征表现及分析

目的:通过研究脑卒中后上肢偏瘫患者H反射的特征表现,及其与偏瘫肢体肌张力的关系,探讨H反射在脑卒中后上肢偏瘫患者神经电生理评定中的应用价值。方法:选择符合本研究入选标准的脑卒中恢复期偏瘫患者42例。分别对患者双侧正中神经、尺神经、桡神经所支配的拇短展肌、小指展肌、指总伸肌进行H反射检查,并对患侧上肢给予改良Ashworth痉挛量表(MAS)评定,确定上述神经中哪些更容易引出H反射,并对其所引出的H反射结果及其与MAS的相关性进行比较和分析。结果:患者双侧正中神经、尺神经所支配的拇短展肌、小指展肌均较易引出H反射,引出率100%。桡神经所支配的指总伸肌不易(3例/42例,引出率7.14%)引出H反射。患侧正中神经和尺神经的H反射潜伏期分别为(25.89±3.66)ms、(25.71±3.26)ms;健侧正中神经和尺神经的H反射潜伏期分别为(26.60±3.11)ms、(26.44±2.87)ms。配对t检验分析,差异均有显著性意义(P<0.05);Hmax/Mmax比值均数用中位数表示,患侧正中神经和尺神经的Hmax/Mmax比值分别为0.185和0.217;健侧Hmax/Mmax比值分别为0.126和0.112,用Wilcoxon符号秩检验分析,患侧与健侧差异均有显著性意义(P<0.05)。用Kruskal-WallisH检验分析显示:患侧上肢正中神经、尺神经H反射潜伏期在MAS不同级别中没有差异,而Hmax/Mmax比值在MAS不同级别中有差异。Spearman秩相关检验结果显示:患侧上肢正中神经H反射潜伏期、Hmax/Mmax比值以及尺神经H反射潜伏期与MAS不相关;而患侧上肢尺神经Hmax/Mmax比值与MAS存在秩相关关系。结论:上肢H反射与MAS存在一定关系,其中Hmax/Mmax比值是评估下运动神经元兴奋性的较好指标,可以成为临床评价痉挛的客观神经电生理指标。     

正常人膈神经和肋间神经重复电刺激的特点

目的：探讨健康人膈神经重复电刺激（PRNS）和肋间神经重复电刺激（IRNS）特点。方法检测了28例健康人双侧PRNS和IRNS,刺激频率3Hz和5Hz,记录第4或第5波与第1波间波幅衰减的百分比。结果：PRNS和IRNS均不存在年龄,性别、侧别间的差异,合并双侧后的结果显示PRNS和IRNS波幅衰减百分比均小于7％。PRNS在操作上难度于大IRNS。结论：可将波幅衰减大于15％作为PRNS和IRNS异常标准。     

健康人膈神经根传导时间初探

目的　初步摸索检测膈神经根传导时间的方法及其在健康人的特点。方法　以表面电极记录 31位健康受试者的 61侧经项磁刺激膈神经根和经颈电刺激膈神经所得的远端运动潜伏期的差。结果　膈神经根传导时间不存在性别及侧别间差异 ,与年龄和身高间不相关。合并不同性别和侧别后健康人的正常值为 (1 .4± 0 .3)ms。结论　膈神经根传导时间是评价与呼吸有关的颈神经根功能的不可缺少的电生理指标。磁刺激膈神经根方法的引入使这一检测易为受试者接受 ,电刺激膈神经使这一检测在操作上更为简便     

Segmental H-reflex studies in upper and lower limbs of patients with radiculopathy

The H-reflex was recorded from the flexor carpi radialis, vastus medialis, and soleus muscles in patients with radiculopathy at C7, L4, and S1 roots. Reflex parameters were compared to normal standards and correlated with other electrophysiologic (eg, electromyography) and clinical evaluations, as well as magnetic resonance imaging scan reports. The H-reflex had significantly smaller peak-to-peak amplitude and longer latency. The stimulus threshold for eliciting the reflexes was substantially higher than normal standards, and the reflex was polyphasic in most patients. A strong correlation was recorded between the pathologic changes in reflex parameters and electrophysiologic and clinical findings of different segmental lesions. Magnetic resonance imaging reports showed moderate correlation with the H-reflex changes. A test of specificity showed that soleus and vastus medialis H-reflexes were 100% specific for lumbosacral segments; flexor carpi radialis was 90% specific for cervical spinal segments. These results indicate that flexor carpi radialis, vastus medialis, and soleus H-reflexes are useful and valid methods for testing C7, L4, and S1 radiculopathy.     

Segmental H-reflex studies in upper and lower limbs of healthy subjects

The H-reflex has been recorded from the flexor carpi radialis muscle in the upper limb and vastus medialis (quadriceps) muscle in the lower limb in relaxed healthy subjects. The characteristics of these reflexes have been compared with those of the soleus H-reflexes, recorded with the same technique, and similar behavior has been reported. The techniques and pitfalls of recording these segmental reflexes and their clinical and neurophysiologic significance are discussed in light of the relevant literature. These segmental reflexes will be useful in studying conduction and integrity of C7, L4, and S1 spinal segments.     

Methodological considerations contributing to variability of the quadriceps H-reflex

The clinical usefulness of the quadriceps H-reflex is limited because of the difficulty of elicitation and its inherent variability in amplitude. In the present study we attempted to identify the influence of methodological variables (head position and remote muscle contractions) on the amplitude of the H-reflex evoked in vastus medialis, vastus lateralis and rectus femoris from the right leg of 13 healthy adult subjects. Square wave stimuli (1-ms duration) were delivered percutaneously to the femoral nerve. The 50% maximal amplitude H-reflexes were evoked while the subject reclined with head facing to the right, left, up and down or while the subject performed Jendrassik's maneuver. The results show a significant increase in the reflex amplitude when the subject's head was turned to the right; there was either a mild increase or no change in amplitude of the response when the subjects faced to the left, up and down. The evoked potential tended to decrease when the subjects closed their eyes; however, the tendency to increase with neck position was not changed. Remote muscle contractions enhanced the amplitude of the response. These results present further evidence of the characteristics of the quadriceps H-reflex and identify postural influences as one controllable source of variability in the L3-L4 root electrodiagnostic test.     

Changes of electrically elicited reflexes in hand and forearm muscles in man

Cutaneo-muscular reflexes with short and long latency excitatory phases following digital nerve stimulation were observed in the first dorsal interosseus muscle of the hand in healthy subjects. The short latency reflex was obtained also with the H-reflex method in the flexor carpi radialis muscle, stimulating the median nerve, with a mean latency (+/- SE) of 15.4 +/- 0.5 ms. The height of the subject correlated with the H-reflex latency. The amplitudes of maximal M-response and maximal H-reflex were higher in athletes than in normals. During weak voluntary contraction of the muscle studied the 50% H-reflex amplitude increased and during passive stretching of wrist flexors the resting amplitude of the 50% H-reflex decreased.     

Contraction-induced upper extremity H reflexes: normative values.

OBJECTIVES: To determine the reliability of contraction-induced upper extremity H reflexes; to calculate normal values for latency, amplitude, and side-to-side variation; and to correlate latency to arm length. DESIGN: Case series. SETTING: Electrophysiology laboratory of a tertiary care center. PARTICIPANTS: Twenty-three healthy volunteers (4 men, 19 women), aged 19 to 42. INTERVENTION: Volunteers were tested bilaterally for H reflexes in four to six upper extremity muscles during an isometric contraction. MAIN OUTCOME MEASURES: H reflex onset latency, onset to negative peak amplitude, side-to-side variation, normal ranges, and latency versus arm-length correlation. RESULTS: H reflexes were found at all 264 sites tested. Mean latencies varied from 9.5 to 27 msec. Maximum normal side-to-side variation was 1.5 to 2.7 msec. Maximum normal amplitude ratios (larger to smaller) ranged from 2.06 to 4.80. Abductor pollicis brevis (APB) and abductor digiti minimi (ADM) H reflex latencies were strongly correlated to arm length. Correlation for APB = .64 (p<.0001) and for ADM = .70 (p<.0001). CONCLUSIONS: Contraction-induced upper extremity H reflexes occur consistently in healthy adults, with latencies, amplitudes, and side-to-side variation occurring in predictable ranges.     

Effect of air-splint application on soleus muscle motoneuron reflex excitability in nondisabled subjects and subjects with cerebrovascular accidents.

We investigated the effect of air-splint pressure on soleus muscle motoneuron reflex excitability in 18 nondisabled subjects with no history of neurological disease and 8 subjects with cerebrovascular accidents (CVAs). Motoneuron reflex excitability was assessed by measuring the percentage of amplitude (peak-to-peak measurement) change in the Hoffman reflex (H-reflex). Pressure was applied for 5 minutes, after which the air-splint was deflated. Ten H-reflexes were recorded and averaged for each subject before pressure application to obtain a baseline value. H-reflexes were also recorded at set intervals during and after pressure application. Two-way analyses of variance for repeated measures were used to compare each group's pressure and postpressure measurements with the baseline value. Significant F tests were followed by post hoc t tests. Analyses of variance were used to compare the nondisabled subjects' H-reflex recordings with those obtained for the subjects with CVAs. The nondisabled subjects demonstrated reductions of 55% at 1 minute, 52% at 3 minutes, and 40% at the fifth minute of pressure application. The postpressure measurements showed increases in the reflex amplitude at 1 and 3 minutes postpressure; however, by the fifth minute, the amplitude was not different from the baseline value. The subjects with CVAs demonstrated reductions of 41% at 1 minute, 48% at 3 minutes, and 52% at 5 minutes of pressure application. None of the postpressure measurements, however, were statistically different from the baseline value. A statistically significant difference was demonstrated between the nondisabled subjects and the subjects with CVAs at the first minute of pressure release.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intramuscular recording of H-reflexes from muscles of the posterior compartment of the lower leg

This study was designed to elucidate the role of different muscles of the posterior compartment of the lower leg in the generation of the surface-recorded H-reflex. H-reflexes were evoked through percutaneous stimulation of the posterior tibial nerve and recorded concurrently, using monopolar electrodes from the soleus (SOL), medial and lateral gastrocnemii (MG and LG), tibialis posterior (TP), flexor digitorum longus (FDL), and flexor hallucis longus (FHL). There were significant (P less than 0.01) differences in the amplitudes, latencies, and modified H:M ratios of the responses recorded from the different muscles. The SOL modified H:M ratios were consistently the highest (x = 1.02), while the H:M ratios for MG (x = 0.34) and LG (x = 0.37) were consistently the lowest. Latencies of H-reflexes obtained from proximal recording sites (x = 29.2 ms) were significantly shorter than those from the most distal site (x = 31.5 ms). These results establish the contribution made by various deep and superficial muscles to the conventionally recorded H-reflex and help explain the differences in H-reflex amplitudes and latencies when recordings are made from different sites.     

Spinal Reflex Arc Excitability Corresponding to the Vastus Medialis Obliquus and Vastus Medialis Longus Muscles

[Purpose] The gross morphology of the vastus medialis (VM) muscle has been thoroughly described. However, there is insufficient evidence of physiological differentiation between the VM obliquus (VMO) and VM longus (VML). To elucidate spinal reflex arc excitability in two divisions of the VM, we compared H-reflexes and T-waves in VMO and VML. [Subjects] Twenty-three healthy male volunteers participated in this study. [Methods] The H-reflex was evoked from the VMO and VML by electrical stimulation of the femoral nerve during knee extension at 10% maximal voluntary isometric contraction. Also, the patellar tendon was tapped by an examiner using an electrical tendon hammer, and a component of the compound muscle action potential (T-wave) was recorded. [Results] The configurations of the H-reflex and T-wave were sharp and slow in VMO and VML, respectively. No significant differences in the amplitudes of the H-reflexes and T-waves were observed between VMO and VML. The durations of VML H-reflexes and T-waves were significantly longer than those in VMO. [Conclusion] Spinal reflex arc excitability corresponding to VMO and VML was similar. However, the configurations and durations of the H-reflex and T-wave were differentiated with electromyography. On the basis of these findings, we suggest that VMO and VML are electrophysiologically distinct entities.Key words: Vastus medialis, H-reflex, T-wave     

Effects of massage on alpha motoneuron excitability.

The purpose of this study was to investigate the specificity of the effects of massage (petrissage) on spinal motoneuron excitability as measured by changes in the peak-to-peak amplitude of H-reflex recordings. H-reflexes (and M-responses) were recorded from the distal aspects of the right triceps surae muscle of 8 men and 8 women, aged 20 to 37 years, with no neuromuscular impairments of the lower extremities. The H-reflexes were recorded during five control and four experimental conditions (20 trials at each condition). The control conditions (C1-C5) preceded and followed each experimental condition, providing a measure of the stability of the H-reflex. Each experimental condition consisted of a 4-minute period of massage of the ipsilateral and contralateral triceps surae and hamstring muscle groups (ITS, CTS, IHS, and CHS, respectively). The mean peak-to-peak amplitude of the H-reflex was found to be stable (range = 1.91-1.95 mV) across the five control conditions. H-reflex amplitudes recorded during the experimental conditions indicate that massage of the ITS resulted in a reduction of the H-reflex (0.83 mV) in comparison with the pretest control condition (C1) and the remaining experimental conditions (range = 1.77-2.23 mV). This difference was significant, and subsequent Newman-Keuls tests indicated a specificity of the effects of massage on the muscle group being massaged. [Sullivan SJ, Williams LRT, Seaborne DE, Morelli M. Effects of massage on alpha motoneuron excitability.     

Flexor carpi radialis motoneuron pool in subjects with chronic carpal tunnel syndrome are more excitable than matched control subjects

We compared excitability of the flexor carpi radialis (FCR) motoneuron pool in subjects with and without carpal tunnel syndrome (CTS). The study involved 11 subjects with chronic idiopathic CTS and 11 asymptomatic subjects as controls. The H-reflex and M-response of FCR muscle were obtained by stimulating the median nerve in the cubital fossa in the presence of an isometric background contraction using surface stimulating and recording electrodes. There was a significantly higher H-reflex latency and amplitude and Hmax/Mmax in CTS subjects (P<0.05). Latency and amplitude of the M-response remained unaffected in CTS group. The results support the hypothesis that central hypersensitivity does occur in chronic CTS. Therefore even in the presence of pathology in peripheral structures central mechanisms should be considered by clinicians.