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

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 : 2025-10-01 Epub 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

Shoulder load during wheelchair-related activities of daily life 日常生活中与轮椅有关的活动中的肩部负荷

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-10-01 Epub Date: 2025-06-20 DOI: 10.1016/j.jelekin.2025.103027

Ursina Arnet , Dirkjan (H. E. J.) Veeger , Wiebe H.K. de Vries

Manual wheelchair users experience significant upper extremity strain, leading to a high prevalence of shoulder pain. Identifying modifiable risk factors for shoulder complaints is crucial for developing effective interventions. Consequently, it’s important to quantify shoulder load (magnitude, frequency and duration) experienced by manual wheelchair users throughout the day.

This study aims to quantify the magnitude of shoulder load during various daily activities, including wheelchair propulsion at different speeds and inclines, ascending and descending ramps, weight relief lift, material handling and desk work. Ten able-bodied participants performed these activities while their upper extremity kinematics and exerted forces were measured. The analysis focused on glenohumeral contact force and rotator cuff muscle forces using the Delft Shoulder and Elbow Model.

Highest mean glenohumeral contact forces were found during weight relief lift (1363 ± 1204 N), followed by descending a ramp (997 ± 1043 N) and fast propulsion (802 ± 742 N). The supraspinatus muscle generated the greatest force during weight relief lift (327 ± 490 N) and fast propulsion (184 ± 205 N). These findings provide a first reference for estimating joint load in daily activities. By combining these data with the individual activity frequency and duration, personalized shoulder load exposure can be assessed, informing the development of targeted interventions to reduce shoulder pain in manual wheelchair users.

手动轮椅使用者会经历明显的上肢劳损，导致肩部疼痛的高发。确定可改变的肩部疾病风险因素对于制定有效的干预措施至关重要。因此，量化手动轮椅使用者全天所经历的肩部负荷（强度、频率和持续时间）是很重要的。本研究旨在量化各种日常活动中肩负荷的大小，包括轮椅在不同速度和倾斜度下的推进，上升和下降的斜坡，减轻重量的升降机，物料搬运和案头工作。10名身体健全的参与者在进行这些活动的同时，测量了他们的上肢运动学和施加的力。使用Delft肩肘模型分析肩关节接触力和肩袖肌肉力。平均肩关节接触力在卸重提升（1363±1204 N）时最高，其次是下降坡道（997±1043 N）和快速推进（802±742 N）。在负重提升（327±490 N）和快速推进（184±205 N）时冈上肌产生的力最大。这些发现为估计日常活动中的关节负荷提供了第一个参考。通过将这些数据与个人活动频率和持续时间相结合，可以评估个性化的肩部负荷暴露，为制定有针对性的干预措施提供信息，以减少手动轮椅使用者的肩部疼痛。

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引用次数: 0

The Probability Density Function (PDF) of surface EMG with increasing force: a comparison between the tibialis anterior and the vastus lateralis 增加力的表面肌电的概率密度函数：胫骨前肌和股外侧肌的比较

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-10-01 Epub Date: 2025-06-20 DOI: 10.1016/j.jelekin.2025.103029

Silvia Recalde-Villamayor , Javier Navallas , Cristina Mariscal , Armando Malanda , Javier Rodriguez-Falces

Objectives

The process by which the surface EMG signal is progressively filled up with motor unit potentials has so far been investigated only in the quadriceps muscles. However, the sEMG filling process is influenced by anatomical, physiological, and neural factors, and thus may be different for each muscle. Here, we sought to characterize the sEMG filling process of the tibialis anterior (TA) and compare it to that of the vastus lateralis (VL).

Methods

Surface EMG signals were recorded from the TA and VL muscles of healthy subjects as force was gradually increased from 0 to 80% MVC. The sEMG filling process was analyzed by measuring the EMG filling factor (FF), an index determined by the shape of the probability density function (PDF) of the sEMG signal.

Results

(1) The sEMG filling process showed significant differences between the TA and VL muscles (p < 0.05).

(2) In the TA, the degree of sEMG filling at the onset of the contraction was low (FF < 0.45) for 72 % of male subjects and 53 % of female subjects, whereas, in the VL, the degree of initial sEMG filling was low for 89 % of male subjects, but only in 12 % of female subjects.

(3) In the TA, the sEMG at high forces (>40 % MVC) contained spikes with largely different amplitudes (FF ∼ 0.5), whereas, in the VL, the sEMG contained spikes with comparable amplitudes (FF ∼ 0.63).

Conclusions

(1) At high forces, the TA PDF was close to Laplacian, whilst the VL PDF was nearly Gaussian; (2) The sEMG filling curves are more informative in the TA than in the VL; (3) The sEMG filling process is muscle and gender specific.

目的：表面肌电信号逐渐充满运动单位电位的过程迄今为止仅在股四头肌中进行了研究。然而，肌电信号填充过程受解剖、生理和神经因素的影响，因此每块肌肉的肌电信号填充过程可能是不同的。在这里，我们试图描述胫骨前肌（TA）的肌电信号填充过程，并将其与股外侧肌（VL）的肌电信号填充过程进行比较。方法记录健康受试者从0 ~ 80% MVC逐渐增加时TA肌和VL肌的表面肌电信号。通过测量表面肌电信号概率密度函数（PDF）的形状决定的表面肌电信号填充因子（FF）来分析表面肌电信号填充过程。结果(1)表面肌和VL肌的表面肌电信号填充过程存在显著差异(p <；(2)在TA区，收缩开始时肌表肌电信号充盈程度较低(FF <；0.45), 72%的男性和53%的女性主题,然而,六世,初始表填写很低程度的男性受试者的89%,但只有12%的女性主题。(3)在助教,面肌电信号在高力量(MVC)在40%包含峰值很大程度上不同的振幅(FF∼0.5),然而,六世,面肌电信号包含峰值与可比振幅(FF∼0.63).Conclusions(1)在高力量,助教PDF接近拉普拉斯算子,而六世PDF近高斯分布;(2)表面肌电信号填充曲线在TA区比在VL区更具信息量；(3)表面肌电信号填充过程具有肌肉和性别特异性。

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引用次数: 0

Passive stretching-induced changes in the spatial distribution of muscle excitation: A step forward in the interpretation of the underlying mechanisms. 被动拉伸引起的肌肉兴奋空间分布的变化：对潜在机制的解释向前迈进了一步。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-10-01 Epub Date: 2025-08-05 DOI: 10.1016/j.jelekin.2025.103046

Nicholas Toninelli, Giuseppe Coratella, Christian Doria, Eloisa Limonta, Marta Borrelli, Susanna Rampichini, Fabio Esposito, Stefano Longo, Emiliano Cè

We assessed passive static stretching (PS) effects on the spatial distribution of muscle excitation (SDME) of the stretched (SL) and contralateral non-stretched limb (CL) during maximum voluntary isometric contractions (MVC). Before (PRE) and after 5-min PS, immediately (POST), at min 5 (POST₅) and 10 (POST₁₀), range of motion (ROM), maximal M-wave (M_max) and MVC of both limbs were assessed in thirty men. During MVC, high-density surface electromyographic signals from the gastrocnemius medialis (GM) and lateralis (GL) were collected. The root mean square (RMS) and centroid coordinates were then obtained. During PS, discomfort perception (VAS), proximal and distal GM architecture were recorded. At POST, ROM increased and MVC decreased together with RMS in both limbs (P < 0.05). A cranio-caudal shift in SDME occurred in both muscles of SL and CL (P < 0.01) that persisted only in SL until POST₅ in GM (P = 0.04), and POST₁₀ in GL (P = 0.01). During PS, VAS was high (>8.0), and fascicle length and angle increased from rest (P < 0.01). No differences between GM portions were found in muscle architecture and in M_max (P > 0.05). The results suggest involvement of central neural mechanisms in SDME shift. The prolonged effect in SL compared to CL indicates a possible additional contribution from mechanical mechanisms.

我们评估了被动静态拉伸（PS）对最大自主等距收缩（MVC）时被拉伸肢体（SL）和对侧非拉伸肢体（CL）肌肉兴奋空间分布（SDME）的影响。对30名男性进行了下肢活动范围（ROM）、最大m波（Mmax）和MVC的评估，分别在5分钟前（PRE）和5分钟后（POST）、5分钟后（POST5）和10分钟后（POST10）。在MVC过程中，收集腓肠肌内侧肌（GM）和外侧肌（GL）的高密度表面肌电图信号。然后获得均方根（RMS）和质心坐标。在PS期间，记录不适感觉（VAS）、近端和远端GM结构。术后两肢ROM升高，MVC降低，RMS均升高(GM组为0.05 (P = 0.04)， GL组为0.10 （P = 0.01）。静息期VAS较高（bbb8.0），肌束长度和角度较静息期增加（pmax）（p>.05）。结果提示SDME的移位涉及中枢神经机制。与CL相比，SL的延长效应表明机械机制可能有额外的贡献。

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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 : 2025-10-01 Epub 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

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 : 2025-10-01 Epub 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

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 : 2025-10-01 Epub 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

Comparing motor unit number estimation techniques 比较运动单元数估计技术

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-10-01 Epub Date: 2025-06-29 DOI: 10.1016/j.jelekin.2025.103030

M.I.B. Debenham , O. Roussel , C.J. McNeil , M.J. Berger , B.H. Dalton

It is unclear how comparable motor unit number estimates (MUNEs) are when derived from a non-invasive technique involving repetitive peripheral nerve stimulation vs. one involving volitional contractions and intramuscular recordings of single motor units (MUs). Therefore, this study examined MUNEs from MScanFit (MScan) and Decomposition-Enhanced Spike-Triggered Averaging (DE-STA). Eighteen participants (8 females, 10 males; 29.7 ± 7.1 years) sat with their right leg positioned in an isometric myograph while surface electromyography (EMG) was recorded from the tibialis anterior (TA). The MScan protocol isolated and derived the size of single MUs by repeatedly stimulating the common fibular nerve at progressively weaker currents to model a compound muscle action potential (CMAP) stimulus–response curve. For DE-STA, a concentric needle electrode was inserted into the TA, and participants performed 30-s isometric dorsiflexion contractions at 25 % of maximal voluntary torque to obtain ≥20 individual surface MU potentials (S-MUPs; i.e., single MUs extracted from the surface EMG signal based on needle-detected spikes). Both techniques used the same maximal CMAP to calculate a MUNE, yet MScan used a mathematical model to simulate the recorded CMAP stimulus–response, which was compared to the recorded scan to minimize disagreement; whereas DE-STA compared the size of the maximal CMAP to the average S-MUP. There was no difference between the MUNE calculated via DE-STA (132 ± 26 MUs) and MScan (142 ± 22 MUs; p = 0.11), and the bias (10.0 MUs) and limits of agreement (67.6 vs −47.6 MU difference) suggests that either technique may independently offer a reasonable MU estimate for the TA of young adults.

目前尚不清楚，重复性周围神经刺激的非侵入性技术与意志收缩和单个运动单位（MUs）的肌肉内记录的技术相比，可比性运动单位数估计（MUNEs）的效果如何。因此，本研究检查了MScanFit （MScan）和分解增强峰值触发平均（DE-STA）的MUNEs。18名参与者(女性8人，男性10人；29.7±7.1岁)坐下，右腿定位于等长肌图，记录胫骨前肌（TA）的肌表电图（EMG）。MScan方案通过以逐渐变弱的电流反复刺激腓骨总神经来模拟复合肌肉动作电位（CMAP）刺激-反应曲线，从而分离并推导出单个MUs的大小。对于DE-STA，将一个同心针电极插入TA，参与者以最大自主扭矩的25%进行30秒的等长背屈收缩，以获得≥20个个体表面MU电位（S-MUPs）；即，根据针检测到的尖峰从表面肌电信号中提取单个mu)。两种技术都使用相同的最大CMAP来计算MUNE，但MScan使用数学模型来模拟记录的CMAP刺激反应，并将其与记录的扫描进行比较，以尽量减少差异；而DE-STA将最大CMAP的大小与平均S-MUP进行比较。通过DE-STA计算的MUNE（132±26 MUs）与MScan计算的MUNE（142±22 MUs）无差异；p = 0.11)，偏差（10.0 MU）和一致性限制（67.6 vs - 47.6 MU差异）表明，这两种技术都可以独立地为年轻人的TA提供合理的MU估计。

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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 : 2025-10-01 Epub 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

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 : 2025-10-01 Epub 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