Journal of Electromyography and Kinesiology最新文献_第6页

Greater distal excitation of the biceps femoris long head reflects proximodistal differences in motor unit action potential properties 股骨长头二头肌远端更大的兴奋反映了运动单位动作电位特性的近端和远端差异

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-09-02 DOI: 10.1016/j.jelekin.2025.103053

José Carlos dos Santos Albarello , Hélio V. Cabral , Francesco Negro , Liliam Fernandes de Oliveira

Evidence on regional muscle excitation within hamstrings remains controversial, primarily because information derived solely from surface electromyograms (sEMG) amplitude does not necessarily provide an accurate estimate of neural drive to the muscle. To address this limitation, this study investigated whether there are proximodistal differences in motor unit properties of the biceps femoris long head during isometric hip extension and knee flexion tasks. Seventeen resistance-trained males performed isometric knee flexion and hip extension tasks at 20 % and 40 % of maximal voluntary contraction. High-density sEMG were recorded from proximal and distal regions of the biceps femoris long head and decomposed into individual motor units. Central motor unit and action potential properties were analyzed. Bipolar sEMG amplitude was also calculated for each region to simulate traditional sEMG measurements. Bipolar sEMG amplitude, motor unit action potential amplitude and conduction velocity were significantly greater in the distal region during both tasks. In contrast, no proximodistal differences were observed in central motor unit properties. These findings suggest that increased bipolar sEMG amplitude in the distal region of the biceps femoris long head is driven by motor unit action potential properties rather than differences in central modulation, likely influenced by intra-muscular variations in muscle mechanics and geometry.

腘绳肌区域肌肉兴奋的证据仍然存在争议，主要是因为仅从表面肌电图（sEMG）振幅获得的信息不一定能准确估计肌肉的神经驱动。为了解决这一局限性，本研究调查了在等距髋关节伸展和膝关节屈曲任务中，股二头肌长头的运动单元特性是否存在近端和远端差异。17名接受阻力训练的男性在20%和40%的最大自愿收缩时进行等距膝关节屈曲和髋关节伸展任务。从股骨二头长头近端和远端记录高密度肌电图，并将其分解为单个运动单元。分析了中枢运动单元和动作电位特性。还计算了每个区域的双极表面肌电信号振幅，以模拟传统的表面肌电信号测量。双极表面肌电信号振幅、运动单位动作电位振幅和传导速度在远端区均显著增大。相比之下，在中枢运动单元特性上没有观察到近端和远端差异。这些发现表明，在股二头肌长头远端区域增加的双极表面肌电信号振幅是由运动单元动作电位特性驱动的，而不是由中枢调节的差异驱动的，这可能受到肌肉力学和几何形状的肌肉内部变化的影响。

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引用次数: 0

Shear wave elastography provides reliable assessments of stiffness in the skin, fascia, and both superficial and deep muscle tissues 横波弹性成像提供可靠的评估刚度在皮肤，筋膜，浅表和深层肌肉组织

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-08-18 DOI: 10.1016/j.jelekin.2025.103050

Cameron D. Ley , Eduardo Martinez Valdes , Conall F. Murtagh , Jonathan Power , Barry Drust

Shear wave elastography (SWE) is a reliable method of estimating stiffness of superficial rectus femoris (RF) muscle at various muscle lengths. Its reliability has not been assessed in deeper muscle regions or its overlying fascia and skin tissue. 20 healthy participants completed two visits in which RF shear wave velocity (SWV) was measured twice, separated by 30mins, at four depths (skin–SKIN, fascia–FAS, superficial muscle–SUP, and deep muscle–DEEP) in three positions (relaxed–REL, neutral–NEU, and stretched–STR). Relative reliability was determined by intraclass correlation coefficients and absolute reliability was assessed by standard error and bias of measurements. SWE reported poor to good relative intra-day reliability (ICC, 0.33–0.82) but good to excellent absolute intra-day reliability (SEM, 0.14–0.25 m/s; bias, −0.12–0.07). Relative SWE inter-day reliability was moderate to excellent (ICC, 0.54–0.91) and absolute reliability was good to excellent (SEM, 0.12–0.21 m/s; bias, −0.05–0.06). Reliability was highest in the order of STR, NEU, REL with regards to position, with SKIN and FAS reliability greater than in muscle. SUP measurements reported greater reliability than DEEP. Therefore, SWE is a reliable method of estimating SKIN, FAS, SUP and DEEP RF tissue stiffness. To optimise repeatability, measurements should be taken from stretched superficial tissue.

横波弹性成像（SWE）是一种可靠的方法估计刚度的浅股直肌（RF）肌肉在不同的肌肉长度。其可靠性尚未评估在深层肌肉区域或其上的筋膜和皮肤组织。20名健康参与者完成了两次访问，在四个深度（皮肤-皮肤，筋膜- fas，浅表肌肉- sup和深层肌肉- deep）三个位置（松弛- rel，中性- neu和拉伸- str）测量RF剪切波速度（SWV），间隔30分钟。相对信度由类内相关系数确定，绝对信度由标准误差和测量偏差评估。SWE报告了较差到良好的相对日内信度（ICC, 0.33-0.82），但良好到优秀的绝对日内信度（SEM, 0.14-0.25 m/s；偏差，- 0.12-0.07）。相对SWE日间信度为中等至优秀（ICC, 0.54-0.91），绝对信度为良好至优秀（SEM, 0.12-0.21 m/s；偏差，- 0.05-0.06）。体位上STR、NEU、REL的信度最高，皮肤和FAS的信度高于肌肉。SUP测量报告的可靠性高于DEEP。因此，SWE是估计SKIN、FAS、SUP和DEEP RF组织刚度的可靠方法。为了优化可重复性，应从拉伸的表面组织进行测量。

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引用次数: 0

Hamstrings corticomotor and neuromechanical function in individuals with anterior cruciate ligament reconstruction 前交叉韧带重建患者的腘绳肌皮质运动和神经力学功能

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-08-18 DOI: 10.1016/j.jelekin.2025.103048

Moein Koohestani , David A. Sherman , Justin L. Rush , Ava L. Schwartz , Grant E. Norte

Hamstrings neuromuscular alterations are common after anterior cruciate ligament (ACL) reconstruction; however, their neural origins remain unclear. While quadriceps corticospinal function after ACL reconstruction (ACLR) is well studied, similar data for hamstrings are lacking. We aimed to assess hamstrings corticomotor and neuromechanical function and their associations in individuals with ACLR. Twenty-three adults with primary, unilateral ACLR via hamstrings tendon autograft were assessed (time from surgery = 46.9 ± 26.3). Corticomotor function was quantified via active motor threshold (AMT), motor evoked potential (MEP), short-interval intracortical inhibition, intracortical facilitation (ICF), and cortical silent period (CSP) in semitendinosus. Neuromechanical function was quantified via maximal voluntary isometric contraction (MVIC) torque, early and late-phase rate of torque development (RTD₁₀₀, RTD₂₀₀), and semitendinosus electromyographic amplitude. Paired-samples t-tests or Wilcoxon signed-rank tests compared outcomes between limbs. Associations between involved limb outcomes were analyzed using correlation coefficients. Involved limbs exhibited shorter CSP (p = 0.005), lower MVIC torque (p = 0.002), and lower RTD₂₀₀ (p = 0.002) than uninvolved limbs. Lower AMT (r = 0.462, p = 0.026) and ICF (r = 0.510, p = 0.013) associated with lower RTD₂₀₀, and lower MEP associated with lower MVIC torque (r = 0.448, p = 0.032). Hamstrings neural adaptation following ACLR, characterized by lower corticospinal inhibition (semitendinosus) and torque deficits, highlights the need for rehabilitation approaches targeting both neural and peripheral impairments.

前交叉韧带（ACL）重建后腘绳肌神经肌肉改变是常见的；然而，它们的神经起源仍不清楚。虽然对前交叉韧带重建（ACLR）后的股四头肌皮质脊髓功能进行了很好的研究，但对腘绳肌缺乏类似的研究数据。我们的目的是评估ACLR患者的腘绳肌皮质运动和神经机械功能及其相关性。本研究评估了23例通过自体腘绳肌腱移植的原发性单侧ACLR成人患者（手术时间= 46.9±26.3）。通过半腱鼠的活动运动阈值（AMT）、运动诱发电位（MEP）、短间期皮质内抑制、皮质内促进（ICF）和皮质沉默期（CSP）对皮质运动功能进行量化。神经力学功能通过最大自主等距收缩（MVIC）扭矩、早期和晚期扭矩发展率（RTD100、RTD200）和半腱肌肌电振幅来量化。配对样本t检验或Wilcoxon符号秩检验比较四肢之间的结果。使用相关系数分析受累肢体预后之间的关联。受累肢体的CSP较短（p = 0.005）， MVIC扭矩较低（p = 0.002）， RTD200较低（p = 0.002）。较低的AMT （r = 0.462, p = 0.026）和ICF （r = 0.510, p = 0.013）与较低的RTD200相关，较低的MEP与较低的MVIC扭矩相关（r = 0.448, p = 0.032）。ACLR后腘绳肌神经适应，以下皮质脊髓抑制（半腱肌）和扭矩缺陷为特征，强调了针对神经和外周损伤的康复方法的必要性。

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引用次数: 0

Estimating maximum acceptable duty cycles (MADC) for overhead exertions 估算开销工作的最大可接受占空比（MADC）

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-08-17 DOI: 10.1016/j.jelekin.2025.103049

Michael W.B. Watterworth, Nicholas J. La Delfa

Overhead work poses a significant risk for shoulder musculoskeletal disorders due to elevated arm postures and sustained loading, yet current ergonomics tools provide limited guidance on the acceptable percentage of time such tasks can be performed. This concept, referred to as the Maximum Acceptable Duty Cycle (MADC), represents the proportion of time within a work cycle that an exertion can be sustained at a psychophysically acceptable level. This study addresses that gap by reconfiguring an existing ergonomics assessment tool for overhead work to estimate MADC, rather than maximum acceptable forces. MADC values across the overhead workspace were mapped using computational modeling of over 800,000 overhead hand positions under three superior-directed load conditions (5, 10, and 20 N). MADC varied substantially with hand position and force demand: at 5 N, values ranged from 0–40 %, while at 20 N, MADC never exceeded 14 %. A consistent ergonomic ‘sweet spot’ was identified slightly above and forward of the shoulder, where MADC is maximized, providing the largest design space for allowable task duty cycles. The reconfigured tool offers actionable, evidence-based guidance for overhead task design by informing duty cycle limits in industrial settings, where current one-size-fits-all thresholds lack empirical justification.

由于抬高的手臂姿势和持续的负荷，头顶工作对肩部肌肉骨骼疾病有很大的风险，但目前的人体工程学工具对此类任务可接受的时间百分比提供了有限的指导。这个概念被称为最大可接受占空比（MADC），它代表了在一个工作周期内，一种努力可以维持在心理上可接受的水平上的时间比例。本研究通过重新配置现有的用于架空作业的人体工程学评估工具来估计MADC，而不是最大可接受力，从而解决了这一差距。在三种优越定向负载条件下（5、10和20 N），通过计算建模绘制了整个架空工作区的MADC值。MADC随手的位置和力的需求变化很大：在5 N时，数值范围为0 - 40%，而在20 N时，MADC从未超过14%。一个符合人体工程学的“最佳点”被确定在肩膀的上方和前方，MADC最大化，为允许的任务工作周期提供最大的设计空间。重新配置的工具通过告知工业环境中的占空比限制，为开销任务设计提供了可操作的、基于证据的指导，而目前的一刀切阈值缺乏经验证明。

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引用次数: 0

Acute effects of different muscle fatigue conditions during strength training on localized muscle bioimpedance in women 力量训练中不同肌肉疲劳状态对女性局部肌肉生物阻抗的急性影响

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-08-17 DOI: 10.1016/j.jelekin.2025.103051

Francisco Dalton-Alves , Taisa Menezes de Andrade , Francisco Kássio Menezes da Silva , Carla Bianca Tabosa Oliveira , Alex Soares Marreiros Ferraz

This study aims to compare the localized muscle bioimpedance (ML-BIA) responses under different muscle fatigue conditions during strength training (ST). Twelve women participated in the study, which followed a crossover, counterbalanced, and randomized design. The experimental sessions were conducted using a 45° leg press machine, consisting of two conditions: a session until muscle failure (MF) and a session with no muscle failure (NMF). ML-BIA was assessed before the sessions, immediately after all sets were completed, and 20 and 30 min post-sessions. The ML-BIA measures of resistance (R), reactance (XC), and phase angle (PA) of the quadriceps were obtained. The countermovement Jump (CMJ) was assessed before and after both conditions. Repeated measures analysis of variance was used to compare conditions, with a significance level set at p < 0.05. In the CMJ test, significant reductions in jump height and power were observed only in the MF condition (p < 0.001). PA showed significant reductions compared to rest only in the MF condition (p < 0.001), with reductions maintained up to 30 min after the session. Our data showed that ML-BIA parameters respond differently under varying fatigue conditions, with PA decreasing only in the higher fatigue condition.

本研究旨在比较力量训练（ST）中不同肌肉疲劳状态下的局部肌肉生物阻抗（ML-BIA）反应。12名女性参与了这项研究，该研究遵循交叉、平衡和随机设计。实验使用45°腿压机进行，包括两种情况：一种是直到肌肉衰竭（MF），另一种是没有肌肉衰竭（NMF）。在训练前、所有训练完成后以及训练后20和30分钟分别对ML-BIA进行评估。ML-BIA测量了股四头肌的电阻(R)、电抗（XC）和相位角（PA）。对两种条件前后的反动作跳跃（CMJ）进行评估。采用重复测量方差分析比较条件，显著性水平设置为p <； 0.05。在CMJ测试中，仅在MF条件下观察到跳跃高度和力量的显著降低（p < 0.001）。与仅在MF条件下休息相比，PA表现出显著的减少（p < 0.001），这种减少在会话后持续30分钟。我们的数据表明，ML-BIA参数在不同的疲劳状态下响应不同，只有在高疲劳状态下PA才会下降。

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引用次数: 0

Does hemiparetic dorsiflexion in swing phase depend on spasticity? 摇摆期偏瘫背屈是否与痉挛有关？

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-08-10 DOI: 10.1016/j.jelekin.2025.103047

Maria Vinti , Mathias Blandeau , Hélène Pillet , Wafa Skalli , Philippe Decq , Andrea Merlo , Jean-Michel Gracies , Nicolas Bayle , Mouna Ghédira , Emilie Hutin

Objective

This study quantified dorsiflexor and plantar flexor (PF) spasticity, and agonist and antagonist recruitment (cocontractions) during the swing phase of gait in individuals with hemiparesis with and without prior tibial neurotomy, investigating the role of spastic cocontraction versus spasticity in limiting dorsiflexion (DF).

Methods

Eleven hemiparetic subjects and 11 controls walking at comfortable and slow velocities underwent kinematic and electromyographic (EMG) analysis of PF and DF muscles. Five of the hemiparetic subjects had undergone tibial nerve neurotomy, which eliminates PF spasticity. Key metrics included ankle dorsiflexion, tibialis anterior recruitment, and coefficients of antagonist activation of gastrocnemius medialis and soleus during swing. Spasticity was assessed using the Tardieu scale.

Results

Controls walking at slow speed showed similar velocity as hemiparetic subjects. Hemiparetic subjects showed reduced ankle dorsiflexion despite higher tibialis anterior recruitment, increased plantar flexor cocontraction before any dorsiflexion, even in neurotomy patients without spasticity.

Conclusions

Increased PF cocontraction persists even in the absence of spasticity, limiting dorsiflexion during swing. Spastic cocontraction, not spasticity, is a primary factor impairing active DF.

Significance

These findings emphasize that targeting spastic cocontraction of plantar flexors may be crucial for improving dorsiflexion and gait rehabilitation in hemiparetic patients, instead of addressing spasticity.

目的：本研究量化偏瘫患者在步态摇摆期背屈肌和足底屈肌（PF）的痉挛，以及激动剂和拮抗剂的招募（收缩），研究痉挛性收缩与痉挛性收缩在限制背屈（DF）中的作用。方法对6例偏瘫患者和11例正常人进行慢速舒适步行的运动和肌电图（EMG）分析。5名偏瘫患者接受了胫骨神经切开术，消除了PF痉挛。关键指标包括踝关节背屈，胫骨前肌恢复，以及在摆动过程中腓肠肌内侧肌和比目鱼肌的拮抗剂激活系数。采用Tardieu量表评估痉挛程度。结果对照组慢速行走速度与偏瘫组相近。偏瘫患者表现出踝关节背屈减少，尽管胫骨前肌收缩增加，在任何背屈之前足底屈肌收缩增加，即使在没有痉挛的神经切开术患者中也是如此。结论：即使在没有痉挛的情况下，PF收缩的增加仍然存在，限制了摆动时的背屈。痉挛性收缩，而不是痉挛，是损害活性DF的主要因素。这些发现强调，针对足底屈肌的痉挛性收缩可能对改善偏瘫患者的背屈和步态康复至关重要，而不是解决痉挛问题。

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引用次数: 0

Tendon overuse models have different effects on tissue mechanical properties in ex vivo bovine tendons 肌腱过度使用模型对离体牛肌腱组织力学性能有不同的影响

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-08-07 DOI: 10.1016/j.jelekin.2025.103043

Zoe M. Moore , Grace Wood , Jake Elliott , Julianna C. Simon , Meghan E. Vidt

Tendinopathy is an overuse injury that occurs in high load bearing tendons, causing decreased function and increased pain. Current tendinopathy treatments produce inconsistent outcomes, creating a need for novel treatments. It is unclear whether current tendinopathy models used to develop new treatments replicate the mechanical effects of the injury. We aim to compare the mechanical properties of 2 established tendinopathy models – collagenase injection and mechanical overload − in ex vivo bovine tendons. Eighteen bovine tendons were split into 3 groups, including: uninjured, collagenase injection (0.5 mL collagenase and 0.5 mL fibrin gel), and mechanical overload (5 cycles of tensile loading/unloading). Mechanical testing of samples was performed. Stiffness, maximum force at failure, and ultimate tensile stress (UTS) were computed, then compared across groups using 1-way ANOVA with significance set at p < 0.05. Results showed maximum force and UTS were reduced for the mechanical overload group (402.1 ± 232.3 N; 9.1 ± 5.3 MPa) versus uninjured (1222.9 ± 270.8 N; 28.9 ± 4.6 MPa) and collagenase injection groups (1309.0 ± 242.1 N; 25.0 ± 8.2 MPa) (all p < 0.001). Stiffness was not different across groups (all p > 0.33). Findings suggest that ex vivo mechanical overload better represents the mechanical properties of tendinopathy than collagenase injection.

肌腱病是一种发生在高负荷肌腱的过度使用损伤，导致功能下降和疼痛增加。目前的肌腱病变治疗产生不一致的结果，需要新的治疗方法。目前尚不清楚用于开发新疗法的肌腱病变模型是否能复制损伤的机械效应。我们的目的是比较两种已建立的肌腱病变模型-胶原酶注射和机械过载-在离体牛肌腱中的力学特性。将18根牛肌腱分为3组，分别为未损伤组、胶原酶注射组（0.5 mL胶原酶和0.5 mL纤维蛋白凝胶）组和机械过载组（拉伸加载/卸载5个循环）。对样品进行力学测试。计算刚度、失效时最大力和极限拉应力（UTS），然后使用单因素方差分析（1-way ANOVA）对各组进行比较，显著性设置为p <；0.05. 结果表明：机械过载组最大受力和UTS降低(402.1±232.3 N；9.1±5.3 MPa)与未损伤(1222.9±270.8 N；28.9±4.6 MPa)和胶原酶注射组(1309.0±242.1 N；25.0±8.2 MPa)(均p <；0.001)。各组间硬度无差异(p >；0.33)。结果表明，体外机械负荷比胶原酶注射更能反映肌腱病变的力学特性。

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引用次数: 0

Electromyographic assessment of agonist and antagonist muscles related to the anterior cruciate ligament following surgical Reconstruction: A Cross-Sectional study 手术重建后与前交叉韧带相关的激动剂和拮抗剂肌肉的肌电图评估：一项横断面研究

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-08-05 DOI: 10.1016/j.jelekin.2025.103044

Ricardo Paredes , Carlos Crasto , António Mesquita Montes , Anabela André , Soraia Pereira , Diana Guedes , Leonel Alves , José L. Arias-Buría

Background

Following anterior cruciate ligament reconstruction (ACLR), neuromuscular control alterations may persist, increasing the risk of reinjury. Objectives: This study aimed to investigate electromyographic (EMG) muscle activation and the co-contraction index (CCI) of ACL-related agonist and antagonist muscles during side-hop tasks in ACLR individuals, offering novel insights into neuromuscular strategies during dynamic tasks. Methods: A cross-sectional study was conducted with 15 ACLR individuals and 15 participants without ACL injury (N-ACLR). Participants performed side-hop tasks while kinematic, kinetic, and EMG data were recorded during the preparatory and loading phases. Statistical analyses were performed at a 95 % confidence level. Results: During ipsilateral side hops, ACLR individuals exhibited higher semitendinosus (ST) activity in the initial contact (IC) and risk phases and increased quadriceps:hamstrings (Q:H) CCI in the risk phase compared to N-ACLR (p < 0.05). In contralateral side hops, ACLR individuals demonstrated higher Q:H CCI in the preparatory phase and higher vastus lateralis:biceps femoris (VL:BF) CCI in the IC and risk phases (p < 0.05). Conclusion: ACLR individuals display altered neuromuscular strategies during side-hop tasks compared to N-ACLR, highlighting adaptations in muscle activation and co-contraction patterns.

背景：前交叉韧带重建（ACLR）后，神经肌肉控制改变可能持续存在，增加再损伤的风险。目的：本研究旨在研究ACLR个体侧跳任务中acl相关激动剂和拮抗剂肌肉的肌电图（EMG）肌肉激活和共收缩指数（CCI），为动态任务中的神经肌肉策略提供新的见解。方法：对15例ACLR患者和15例无ACL损伤（N-ACLR）的参与者进行横断面研究。在准备和加载阶段，参与者进行侧跳任务，同时记录运动学、动力学和肌电图数据。统计分析在95%的置信水平上进行。结果：与N-ACLR相比，在同侧跳跃期间，ACLR个体在初次接触（IC）和危险阶段表现出更高的半腱肌（ST）活性，并且在危险阶段表现出更高的股四头肌：腘绳肌（Q:H） CCI (p <；0.05)。在对侧跳跃中，ACLR个体在准备阶段表现出较高的Q:H CCI，在IC和危险阶段表现出较高的股外侧：股二头肌（VL:BF） CCI (p <；0.05)。结论：与N-ACLR相比，ACLR个体在侧跳任务中表现出改变的神经肌肉策略，突出了肌肉激活和共同收缩模式的适应。

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引用次数: 0

Diagnostic value of EMG of sternocleidomastoid and trapezius in assessing bulbar lower motor neuron involvement in amyotrophic lateral sclerosis patients 胸锁乳突肌和斜方肌肌电图对肌萎缩侧索硬化症患者球下运动神经元受累的诊断价值

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-07-23 DOI: 10.1016/j.jelekin.2025.103040

Jiarui Zhao , Jiongming Bai , Hongfen Wang , Ying Zhang , Jinghong Zhang , Yahui Zhu , Xinyuan Pang , Zhaohui Chen , Li Ling , Hongmei Cheng , Mao Li , Xusheng Huang

The diagnostic value of needle electromyography (EMG) of sternocleidomastoid (SCM) and trapezius (TRA) in assessing bulbar lower motor neuron involvement (LMN) remained controversial. 203 sporadic amyotrophic lateral sclerosis (ALS) patients were enrolled to assess the correlation between EMG abnormalities in SCM and TRA and bulbar LMN involvement. Additionally, difference analysis and diagnostic consistency analysis of EMG abnormalities in GEN (genioglossus), SCM, and TRA were compared. Finally, separate effects of EMG abnormalities in GEN, SCM, and TRA on diagnostic gradings were examined according to the Awaji-Shima criteria. 22 (18.2 %) and 65 (53.7 %) patients without bulbar LMN involvement showed EMG abnormalities in SCM and TRA. In contrast, 19 (23.2 %) and 11 (13.4 %) patients with bulbar LMN involvement showed normal EMG results in SCM and TRA. Multivariate logistic regression analyses showed that both EMG abnormalities in SCM and TRA were correlated with bulbar LMN involvement (P < 0.001). SCM showed electrophysiological characteristics similar to GEN when compared to TRA. However, TRA (67.0 %) showed significantly higher rates of EMG abnormalities than SCM (41.9 %) and GEN (40.4 %) in the whole study population. Reclassified diagnostic gradings showed no significant difference when evaluating EMG abnormalities in individual muscles to indicate bulbar LMN involvement (P = 0.072). EMG abnormalities in SCM and TRA could not fully represent bulbar LMN involvement but were correlated with it. It’s advisable to prioritise TRA as a better option when a patient cannot tolerate an EMG examination in the GEN. To enhance the diagnostic evaluation, an EMG examination of GEN could be served as the last choice.

胸锁乳突肌（SCM）和斜方肌（TRA）的针肌电图（EMG）在评估球下运动神经元受累（LMN）中的诊断价值一直存在争议。203例散发性肌萎缩性侧索硬化症（ALS）患者被纳入研究，以评估SCM和TRA肌电图异常与脊髓LMN受累的相关性。此外，比较GEN （genigenogssus）、SCM和TRA的肌电异常的差异分析和诊断一致性分析。最后，根据Awaji-Shima标准，分别检查GEN、SCM和TRA的肌电异常对诊断分级的影响。22例（18.2%）和65例（53.7%）未受累的患者在SCM和TRA表现出肌电异常。相比之下，19例（23.2%）和11例（13.4%）受累于球LMN的患者在SCM和TRA上的肌电图显示正常。多因素logistic回归分析显示，SCM和TRA的肌电图异常与球部LMN受累相关(P <；0.001)。与TRA相比，SCM表现出与GEN相似的电生理特征。然而，在整个研究人群中，TRA（67.0%）的肌电异常率明显高于SCM（41.9%）和GEN（40.4%）。重新分类的诊断分级在评估单个肌肉的肌电图异常以指示球LMN受累时没有显着差异（P = 0.072）。SCM和TRA的肌电异常不能完全代表LMN受累，但与之相关。当患者不能忍受GEN肌电图检查时，建议优先考虑TRA作为更好的选择。为了提高诊断评价，GEN肌电图检查可以作为最后的选择。

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引用次数: 0

Algorithm for jitter measurement in neuromuscular junction disease 神经肌肉交界处疾病的抖动测量算法

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-07-17 DOI: 10.1016/j.jelekin.2025.103042

Armando Malanda , Daniel Stashuk , César Valle , Javier Rodríguez-Falces , Javier Navallas , Mamede de Carvalho , José Castro , Oscar Garnés-Camarena

The objective of this work was to extend the evaluation of a recently proposed method for estimating neuromuscular jitter within motor unit potential (MUP) trains extracted from muscles suffering neuromuscular junction disease. The method detects, within the MUP duration, “single-fiber” intervals that have likely been produced by single muscle fibers. Jitter is then estimated between pairs of these “single-fiber” intervals using an algorithm which incorporates the traditional mean consecutive difference (MCD) parameter.

Electromyographic (EMG) recordings from facial muscles of 15 patients with symptoms related to myasthenia gravis were obtained. MUP trains were extracted using DQEMG software and manual jitter measures were obtained using an ad-hoc graphical interface, which emulates single fiber EMG protocols. Automatic measures for two different values of an internal threshold parameter were obtained and compared to manual measures. 5 %, 25 %, 75 % and 95 % percentiles for the differences between the automatic and manual jitter measurements were [−3.74, −1.47, 1.24, 3.47 μs] and [−6.45, −2.07, 1.65, 7.16 μs], for the two threshold values, respectively. Therefore, very small statistical and clinical differences were found between the automatic and manual jitter measures, supporting the method as an accurate tool for jitter assessment or as a guiding aid for manual procedures.

这项工作的目的是扩展评估最近提出的一种方法，用于估计从患有神经肌肉连接疾病的肌肉中提取的运动单位电位（MUP）训练中的神经肌肉抖动。该方法在MUP持续时间内检测可能由单个肌肉纤维产生的“单纤维”间隔。然后使用结合传统平均连续差（MCD）参数的算法估计这些“单光纤”间隔对之间的抖动。本文对15例有重症肌无力相关症状的患者进行了面部肌电图（EMG）记录。使用DQEMG软件提取MUP列车，并使用模拟单光纤肌电信号协议的自组织图形界面获得手动抖动测量。获得了内部阈值参数的两个不同值的自动测量值，并与手动测量值进行了比较。自动抖动测量值与手动抖动测量值差异的5%、25%、75%和95%的百分位数分别为[- 3.74、- 1.47、1.24、3.47 μs]和[- 6.45、- 2.07、1.65、7.16 μs]。因此，自动和手动抖动测量之间的统计和临床差异非常小，支持该方法作为抖动评估的准确工具或作为手动程序的指导辅助。

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引用次数: 0