Quantitative comparison of motor unit potential parameters between monopolar and concentric needles

This study quantitatively compared the simultaneous recording of the "same" motor unit potentials recorded by closely positioned concentric and monopolar needles. The motor unit potentials from the anterior tibialis of 12 young subjects were analyzed independently by both needles being connected to 2 sets of EMG-computer combinations. Recordings of the same motor unit potentials were confirmed by triggering and averaging of the 2 sets of motor unit potentials with identical firing patterns on both EMG screens. Automatic analysis disclosed the monopolar recordings had a significantly higher mean amplitude (2.05 times), larger surface area (2.64 times), and longer duration (1.86 times) than the concentric recordings, while the mean number of phases (1.58 times) and turns (1.35 times) revealed no statistical differences. Both active recording and reference electrodes contributed to these differences.     

Concentric or monopolar electrode for jitter determination in orbicularis oculi

Objectives

To investigate if monopolar (MN) and concentric (CN) electrodes are equivalent for volitional contraction jitter estimation in orbicularis oculi (OO), and to study the effect of selecting a specific high-pass filter.

Normal needle electromyographic insertional activity morphology: A clinical and simulation study

Needle electromyographic insertional activity waveform morphology, and mechanisms of generation, have received little attention. This study analyzes the individual component waveforms that contribute to the burst of electrical activity known as insertional activity. One hundred monopolar needle insertions were slowly performed and high speed recorded to allow better separation of the contributing individual component waveforms. Analysis of the many waveforms recorded demonstrates several classes of potentials. All of these could be reconstructed by the summation of two basic or elementary waveform patterns: a biphasic initially negative spike with or without a “prepotential” similar to an end-plate spike, and the biphasic initially positive spike with a slowly declining negative phase, similar to a positive sharp wave, though shorter in duration. The relationship between these elementary waveforms and their hypothesized generator sources is discussed. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21:910–920, 1998.     

AAEM minimonograph #11: Needle examination in clinical electromyography

The physiologic and histologic principles underlying clinical electromyographic studies are briefly reviewed as an introduction to the normal and abnormal findings in human subjects. Technical aspects of recordings as well as the specific types of discharges and their significance are discussed.     

A prospective double-blind clinical trial, comparing the sharp Quincke needle (22G) with an "atraumatic" needle (22G) in the induction of post-lumbar puncture headache

Posture-dependent, post-lumbar puncture headache is most likely caused by continuous leakage of cerebrospinal fluid through the dura mater perforation with a consecutive downward sagging of the intracranial content and an irritation of pain-sensitive structures of meninges and blood vessels. A psychogenic co-factor may also play a role. It is generally acknowledged that the incidence and intensity of the headache correlate significantly with the diameter of the needles used. A second factor, the shape of the needle point plays a crucial role as is shown in our prospective, double-blind, clinical trial with 75 patients: employment of the "atraumatic" Sprotte needle with a rounded off point significantly reduced the incidence of post-puncture headache from 36% to 4%. Beside the discussion of pathogenic factors, remarks on a rational therapy are made.     

重症肌无力患者针电极肌电图肌源性受损表现的临床意义

目的分析重症肌无力(myasthenia gravis,MG)患者针电极肌电图(needle electrode electromyography,NEMG)检查结果的临床意义。方法回顾性分析2011-01-01—2013-12-31期间在解放军第309医院神经内科住院治疗的335例确诊MG患者的NEMG检查结果和临床资料,根据NEMG检查是否出现肌源性受损表现将患者分为两组,对比分析两组患者的临床特点。结果29例(8.7%)NEMG出现肌源性受损表现,异常NEMG均无自发电位,仅表现为运动单位电位(motor unit potential,MUP)波幅降低、时限缩短。NEMG检查有肌源性受损表现组临床绝对评分(20.8±7.3)高于无肌源性受损表现组(14.9±9.0,t=1.79,P0.05)。NEMG检查无肌源性受损表现者多以眼外肌无力为首发症状(85.62%),以肢体和球部肌肉起病者比例较低(14.38%);与无肌源性受损表现者相比,有肌源性受损表现者以眼外肌为首发症状者比例较低(55.17%),多以肢体和球部肌肉受累起病(44.83%),两组差异有统计学意义(χ2=9.79,P0.01)。两组间比较,性别、发病年龄、病程、Osserman分型及胸腺病理类型差异均无统计学意义(均P0.05)。结论 NEMG检测表现为肌源性受损者病情较无肌源性受损表现者重。电生理检查可在一定程度上提示MG病情的严重程度。     

应用有限元对比分析椎体成形术中单侧入路退针法与双侧固定点注射骨水泥的生物力学变化

背景：要使椎体成形术单侧入路获得双侧入路的力学分布效果，需要改进单侧入路的穿刺路径及注射方法。在前期临床实践中作者设计了三维穿刺导向器，在其导引下穿刺到位理想，采用退针注射法注射骨水泥，使得骨水泥在椎体内分布更加合理，临床效果得到了提高，但是否在力学分布上与双侧相同？ 目的：应用有限元分析椎体成形过程中单侧入路退针法注射骨水泥的生物力学变化，并与双侧固定点注射骨水泥的方法对比。 方法：采用的原始影像来自一位男性患者，76岁，L1椎体骨质疏松性疼痛。患者伤椎采用单侧入路退针法注射实施椎体成形术，进针点选择左侧椎弓根近中心部位，内倾角度为24.5°，先将针穿刺到达椎体的前中1/3部位，注射骨水泥3 mL，然后缓慢向后退针至椎体的1/2部位，并停留3 min，注射2 mL，再退针到椎体的中后1/3部位注射1 mL。模拟双侧入路，每侧注入3 mL骨水泥，获取椎体L1~2节段断层图像，分别建立有限元模型，对椎体上表面分别依次施加载500，1 000， 1 500，2 000，2 500 N的轴向压缩负载，进行生物力学对比分析。 结果与结论：随着施加负载的增加，应变和应力也逐渐增加，椎体呈现弹性性质，出现了近似线性的小变形情况。双侧固定点和退针注射法注射骨水泥在轴向压缩不同负载下应力和应变差异无显著性意义(P > 0.05)。提示椎体成形过程中单侧入路退针注射法和双侧固定点注射骨水泥的生物力学分布无明显差异。     

应用有限元法对比分析单侧入路退针法与固定点注射骨水泥椎体成形的

采用1例L1椎体骨质疏松性骨折疼痛患者的原始影像资料，男，70岁，患者伤椎采用单侧入路退针法注射实施椎体成形术，进针点选择左侧椎弓根近中心部位，内倾角度为24.5°，先将针穿刺到达椎体的前中1/3部位，注射骨水泥3 mL，然后缓慢向后退针至椎体的1/2部位，并停留3 min，注射2 mL，再退针到椎体的中后1/3部位进行注射1 mL。模拟传统的将全部6 mL骨水泥在椎体中前1/3固定点一次性注入方法，获取椎体L1~2节段断层图像，分别建立有限元模型，对椎体上表面分别依次施加载500，1 000，1 500，2 000，2 500 N的轴向压缩负载，进行生物力学对比分析。随着施加负载的增加，应变和应力也逐渐增加，椎体呈现弹性性质，出现了近似线性的小变形情况。传统注射较退针注射有较大的应力和应变。结果提示，退针注射法注射骨水泥，较传统的一次性固定点注射法有更好的生物力学分布。     

Ultrasound in EMG‐Guided Biopsies: A Prospective,Randomized Pilot Trial

Introduction: At our institution, core muscle biopsies are performed on muscles selected using electromyography (EMG). Ultrasound (US) guidance is not used routinely. The aim of this study was to determine if US guidance of EMG selected muscles would increase the diagnostic yield of the biopsy as compared to the current practice standards. Methods: Two trained physicians performed 40 randomized biopsies (US guided or traditional approach). The amount of tissue obtained in each biopsy was recorded (volume and mass), along with the final pathologic diagnosis in each case and incidence of complications. Results: Forty patients were studied. Sixteen muscle biopsies were done with US guidance; 50% had a definitive diagnosis, and 38% did not. In the non‐US guidance group, 58% had a definitive diagnosis, and 33% did not. Conclusions: US did not provide any additive advantage when used to guide biopsy in a muscle previously selected for biopsy with EMG. Muscle Nerve 54 : 786–788, 2016     

Novel measurement for automated interference pattern analysis of the diaphragm

The automated interference pattern analysis for limb muscles was modified to take into account the unique features of the needle EMG of the diaphragm. The modification was successful in recording more accurately the number of small and large segments and the activity levels with inspiratory effort. “Clouds” were generated in ten healthy subjects. The techniques may prove useful in electrophysiological investigations. © 1997 John Wiley and Sons, Inc.     

槽型鞘脑穿刺针的设计及动物实验初步结果

目的测试槽型鞘脑穿刺针用于实验动物脑组织穿刺的可操作性和安全性。 方法新西兰兔6只,麻醉后骨窗开颅显露双侧大脑半球,左侧大脑半球以传统脑穿刺针进行穿刺,右侧以槽型鞘脑穿刺针穿刺,完成穿刺、拔出穿刺针留置槽形鞘、置管后拔出槽形鞘等步骤。拔出穿刺针后穿刺道以苏木素染色,观察30 min后处死实验动物,提取脑组织,沿脑组织穿刺道制3 μm厚切片,常规HE染色,显微镜下观察脑组织穿刺道病理解剖学变化（脑组织破损及出血情况）,评估损伤程度。 结果2种穿刺针穿刺操作后均会造成穿刺道局灶性脑挫裂伤,表现为穿刺道组织缺损、脑组织淤血、水肿。光镜下可见穿刺道脑组织破碎、细胞排列不规则、水肿的细胞体增大和细胞核固缩,穿刺道外围细胞结构正常。2种穿刺针针道脑组织病理特征差别不明显。 结论槽型鞘脑穿刺针穿刺操作简便,通过槽型鞘置入引流管方便,脑组织损伤程度与传统脑穿刺针无明显差别。     

Comparison between concentric needle EMG and macro EMG in patients with a history of polio.

OBJECTIVES: Acute poliomyelitis causes degeneration of anterior horn cells, followed by denervation. Reinnervation and muscle fibre hypertrophy are mechanisms that compensate this loss of neurones. Concentric needle EMG (CNEMG) and macro EMG are two methods to assess the magnitude of initial involvement and the compensatory reinnervation. The aim of this study is to explore the difference between CNEMG and macro EMG describing the status of the motor unit in patients previously affected by polio. METHODS: Macro and concentric needle EMG investigations were performed in 261 muscles in 121 patients with a remote history of polio. RESULTS: CNEMG was abnormal in 211 muscles, macro EMG was abnormal in 246 muscles. The macro amplitude was 3-4 times 'more abnormal' than CNEMG amplitude relative to the reference values. CNEMG duration was less abnormal and showed only weak correlation with macro amplitudes. The most likely explanation for the difference in magnitude of deviation from reference values for CNEMG and macro EMG, is a more pronounced 'phase cancellation' between single fibre action potentials in CNEMG. This is supported by simulation studies reported here. CONCLUSIONS: In conclusion macro EMG better reflects the size of the motor unit than the CNEMG. For detection of concomitant disorders, CNEMG is the method of choice.     

术中磁共振实时影像导航下穿刺活检术的临床初步应用

目的 探讨术中磁共振(iMRI)影像导航应用于穿刺活检术的临床初步经验、优势与不足.方法 在0.15T PoleStar N-20 iMRI实时影像引导下,对6例颅内占位性质不明患者进行穿刺活检术.结果 6例均获得组织病理学诊断,活检阳性率为100%;1例颅内多发占位患者术后并发左基底节活检区域局限性血肿.结论 iMRI影像导航能及时纠正术中脑移位,即只有当iMRI确定穿刺针已位于病灶内才进行活检,从而有利于提高活检阳性率,减少术后并发症.     

Diagnostic value of electrical stimulation of lumbosacral roots in radiculopathies*

Needle electrical stimulation of the lumbosacral roots at the laminar level of the Th12-L1 or L1-2 intervertebral spaces were performed in 24 normal subjects and 58 patients with various kinds of lumbar radiculopathy (unilateral L4, L5 and S1 herniated nucleus pulposus and lumber stenosis). The root stimulation method was compared with conventional needle EMG. Lumber electrical stimulation showed root abnormalities objectively in 80% of patients while the diagnostic value of needle EMG was 65%. Therefore, electrical root stimulation is superior to routine EMG for localizing lumbar root involvement. However, the only needle EMG demonstrated the root pathology in 7 cases (12%) and single electrophysiological abnormality was found by the root stimulation in 16 cases (27%). Thus, both electrophysiological methods should be complementary to each other in evaluation of the lumbar radiculopathy.     

Low frequency of post-lumbar puncture headache in demented patients

The frequency of post-lumbar puncture headache (PLPH) was registered prospectively in 395 consecutive demented patients at a dementia diagnostic unit. The incidence of PLPH was low, occurring in only 8 patients (2.0%), the severity was mild, and the duration was less than 2 days in all cases but one. The reasons for this low frequency of PLPH in patients with dementia disorders may include disease- and/or age-related low pain sensitivity, rigid dural fibres and arteriosclerotic vessels, and large CSF space due to cerebral atrophy. Analysis of CSF is essential to identify secondary causes of dementia, preferentially chronic infections. The low frequency and severity of PLPH found in the present study shows that, with low risk of complications, lumbar puncture can be included in the routine clinical examination of demented patients.     

浮针疗法联合康复训练对脑卒中偏瘫患者的作用

目的分析浮针疗法联合康复训练对脑卒中偏瘫患者的作用。方法选择我院2014-02—2015-08收治的90例脑卒中偏瘫患者为研究对象,按随机数字的方法分为观察组和对照组,对应数字偶数为观察组,奇数为对照组,每组45例。对照组行常规康复训练治疗,观察组采用浮针疗法联合康复训练进行治疗,比较2组治疗前后的Barthel指数、Fugl-Meyer评分及临床症状积分,并评价临床治疗效果。结果观察组总有效率为91.11%(41/45),明显高于对照组的71.11%(32/45),差异有统计学意义(P0.05);治疗后2组临床症状积分较治疗前显著降低(P0.05),观察组降低更明显,差异有统计学意义(P0.05);治疗后2组Barthel指数、Fugl-Meyer评分均较治疗前显著提高,差异有统计学意义(P0.05),与治疗后对照组比较,观察组提升更明显,差异具有统计学意义(P0.05)。结论浮针疗法联合康复训练可对脑卒中偏瘫患者的临床症状起到改善作用,提高临床治疗效果,改善患者日常生活能力和肢体运动功能,值得临床推广使用。