Journal of Electromyography and Kinesiology最新文献

Neuromechanical adaptation of a perturbation protocol during treadmill running

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-24 DOI: 10.1016/j.jelekin.2025.102989

Mina Khajooei, Andrew Quarmby, Frank Mayer, Tilman Engel

The ability to adapt to unexpected changes in environments is associated with the risk of running-related injuries. Although gait retraining programs can mitigate injury risk, there is a scarcity of studies focusing on neuromechanical adaptations during running with unpredictable perturbations. Hence, the current experiment aimed to analyse spatial–temporal and muscle activity adaptation during a perturbed running protocol. 23 participants performed a 5-minute unperturbed and an 8-minute perturbed running trial with a baseline velocity of 2.5 m/s. During the perturbation protocol, 30-one-sided decelerative perturbations were randomly applied to both legs. Spatial-temporal data and muscle activity of twelve lower extremity and trunk muscles were recorded during unperturbed and perturbed steps. Linear mixed models with repeated measures were applied to identify adaptation at any time point in the data. Statistical analysis indicated adaptation to the perturbation trial in comparison to baseline trial for step duration, length, width and upper- and lower-leg muscles. Adaptations characterized by decreased step duration and length and increased step width and muscle activity. This study has demonstrated participants’ ability to adapt their movement and muscle activity patterns while running with unpredictable perturbations. Therefore, introducing more diverse or novel perturbation stimuli to the human system may be necessary to continually challenge adaptation.

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引用次数: 0

Energetic and neuromuscular impact of running on even or uneven surfaces in standardized laboratory conditions

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-06 DOI: 10.1016/j.jelekin.2025.102987

Simone Bettega , Lorenzo Bortolan , Federico Stella , Cantor Tarperi , Federico Schena , Barbara Pellegrini , Chiara Zoppirolli

Purpose

We examine the energetic and neuromuscular effects of running on even (E-T) and uneven terrains (UE-T) by creating smooth and rough conditions on a standardized circuit.

Methods

Ten adults (age 32.1 ± 7.6 years, body mass 62.2 ± 7 kg, height 167.5 ± 4.2 cm) ran on an ‘iterative-8-shaped’ path. For UE-T, solid hemispheres were fixed to a perforated mat, while for E-T, visible marks guided foot placement. Participants performed two 6-min trials on both terrains in a counterbalanced order, maintaining consistent running patterns and low-intensity speed with a metronome to guide step frequency. This ensured consistency in the timing and positioning of foot placement between the two conditions. Cardio-metabolic parameters were measured continuously, and muscle activation was recorded from six leg muscles using surface EMG.

Results

The analysis showed significantly higher cardio-metabolic responses in UE-T compared to E-T, with increases in oxygen cost (+18 %), energy cost (+23 %), respiratory frequency (+7%), ventilation (+19 %), heart rate (+10 %), and RPE (+50 %) (all p < 0.05). Electromyographic activation of the tibialis anterior (+22 %) and peroneus longus (+10 %) also increased in UE-T.

Conclusions

These findings indicate that running on uneven terrain demands more energy and greater activation of ankle stabilizers, as required in off-road and trail running.

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引用次数: 0

What are my muscles up to? The contribution of surface electromyography to clinical decision-making

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-05 DOI: 10.1016/j.jelekin.2025.102988

Catherine Disselhorst-Klug

Muscles move the body. The varying levels of movement precision needed daily results from a complex interplay within the central nervous system, muscles and sensory feedback, referred to as neuromechanics. This neuromechanical interplay is often impaired in pathology. Although, diagnosis and therapy would benefit from information about the patient’s specific neuromechanical control, no procedures have yet been established in clinical practice that allow this information to be fully recorded. Surface electromyography (sEMG) links neuronal input and muscle function and helps to understand how the CNS orchestrates the multitude of possibilities the neuromusculoskeletal system has at its disposal to solve a movement task. This 2024 Basmajian-Lecture-Paper will highlight sEMG applications in physiological and pathological conditions, to illustrate the potential contribution of sEMG to clinical decision-making. Focussing first on infants’ motor development, it will contribute to the discussion on how neuromechanics and motor skills develop. Continuing with considerations on motor unit activation in health and disease and describing the difference between physiological and pathological muscle coordination in dynamic conditions, it aims to address the possibilities but also the limitations of sEMG in clinical applications. Finally, the influence of robotic support on neuromechanical control and thus on re-learning of motor skills are discussed.

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引用次数: 0

Electrical cutaneous stimulation of the foot sole does not enhance rate of torque development during maximal effort isometric plantarflexion in females 足底皮肤电刺激不能提高女性在最大力度等距跖屈时的扭矩发展速度。

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-01 DOI: 10.1016/j.jelekin.2024.102974

Laura C. Marrelli , Tushar Sharma , Davis A. Forman , Giacomo G. Passarelli , Chioma Nwebube , Avery Hinks , Geoffrey A. Power , Leah R. Bent

Rate of torque development (RTD) measures how rapidly one can generate torque and is crucial for balance and athletic performance. Fast RTD depends on the rapid recruitment of high threshold motor units (MUs). Cutaneous electrical stimulation has been shown to alter MU excitability, favoring high threshold MUs via reduced recruitment thresholds. A strong coupling exists between foot sole cutaneous mechanoreceptors and motor neurons of lower-limb muscles, yet it remains unknown if cutaneous input can impact RTD via modulation of MU excitability. This study aimed to investigate whether electrical stimulation across the heel could alter plantarflexion RTD. 11 young and healthy females underwent eight sets of five explosive isometric plantarflexion contractions on a dynamometer while sitting with hip, knee and ankle angles of 80°, 110°, and 90°, respectively. All participants achieved > 95 % voluntary activation of their plantar flexors. Four sets of contractions were performed with heel cutaneous electrical stimulation (1.0 ms pulses delivered at 300 Hz, at 2 × perceptual threshold) and four sets with no stimulation. Instantaneous RTD values were analyzed in 25 ms epochs from onset to 250 ms. No significant differences were observed between stimulation conditions within each epoch, thus our results suggest that electrical cutaneous stimulation does not alter RTD in this population.

扭矩发展速率（RTD）衡量一个人产生扭矩的速度，对平衡和运动表现至关重要。快速RTD依赖于高阈值运动单元（MUs）的快速募集。皮肤电刺激已被证明可以改变MU的兴奋性，通过降低招募阈值而有利于高阈值MU。足底皮肤机械感受器与下肢肌肉运动神经元之间存在强耦合，但皮肤输入是否可以通过调节MU兴奋性来影响RTD尚不清楚。本研究旨在探讨电刺激是否能改变足跟屈曲RTD。11名年轻健康女性分别以髋部、膝关节和踝关节角度为80°、110°和90°坐着，在测力计上进行了8组5次爆发性跖屈收缩。所有参与者的足底屈肌自发活动达到了95%。采用足跟皮肤电刺激（1.0 ms脉冲，300 Hz， 2倍知觉阈值）进行4组收缩，无刺激进行4组收缩。瞬时RTD值在起始至250 ms的25 ms周期内进行分析。在每个时期的刺激条件之间没有观察到显着差异，因此我们的结果表明皮肤电刺激不会改变该人群的RTD。

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引用次数: 0

Strength and endurance of the lumbar extensor muscles and their predictors: A cross-sectional study in healthy subjects 腰伸肌的力量和耐力及其预测因素：健康受试者的横断面研究

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-01 DOI: 10.1016/j.jelekin.2024.102973

Daniela Vlazna , Blanka Adamova , Peter Krkoska , Viktoria Kokosova , Katerina Matulova , Tamara Barusova , Michaela Sladeckova

The purpose of this cross-sectional study was to present the values of maximal isometric lumbar extensor muscle strength (MILEMS) and lumbar extensor muscle endurance (LEME) in healthy subjects and to study the influence of physiological factors on these parameters. MILEMS using a hand-held dynamometer in three positions (prone, sitting, standing) and LEME using the Biering-Sørensen test were assessed in 115 healthy volunteers. The MILEMS measurements for the specific positions were correlated with each other (Pearson correlation coefficients 0.31–0.87, p < 0.001). In univariable linear regression, sex showed the highest effect on MILEMS prediction in sitting position (higher strength in men, P < 0.001, R² of 20.4 %). Multivariable linear regression led to construction of a calculator to estimate predicted MILEMS in the sitting position in relation to sex, age and BMI with R² of 32.2 %. LEME was mostly predicted by BMI (decrease of LEME with increasing BMI, P < 0.001), but multivariable regression analysis did not allow the construction of a reliable calculator to predict this parameter. In conclusion, we provided values for MILEMS and LEME. A calculator was developed to predict MILEMS and to determine the percentile of measured MILEMS in an individual. It is expected to be particularly useful in assessing patients who are likely to have lumbar extensor muscle impairment.

本横断面研究的目的是了解健康受试者最大等肌伸肌力量（MILEMS）和腰伸肌耐力（LEME）的值，并研究生理因素对这些参数的影响。对115名健康志愿者进行了三种体位（俯卧、坐姿、站立）使用手持式测功机的MILEMS和使用biering - s - ørensen试验的LEME评估。特定位置的MILEMS测量结果彼此相关（Pearson相关系数为0.31-0.87，p 2为20.4%）。多变量线性回归构建了一个计算器来估计与性别、年龄和BMI相关的坐姿预测MILEMS， R2为32.2%。LEME主要由BMI预测(LEME随BMI升高而降低，P

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引用次数: 0

Measurement of voluntary activation of abdominal flexors using transcranial magnetic stimulation 经颅磁刺激测量腹屈肌的主动激活。

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-01 DOI: 10.1016/j.jelekin.2024.102961

Olivia Szepietowski , Hanne Ertman , Shin-Yi Chiou , Paul H. Strutton

Background

Transcranial magnetic stimulation (TMS) has been used to assess voluntary activation (VA) of limb and back muscles, however its ability to assess abdominal muscle VA is unknown. The assessment of abdominal muscle VA using TMS could be applied to patients with trunk dysfunction to enable further understanding of the neurophysiology of trunk control, inform practice and enable the development and monitoring of rehabilitation programmes.

Aim

The aim of this study was to investigate use of TMS and the twitch interpolation technique to measure voluntary activation of abdominal muscles.

Methods

Twenty healthy participants performed sets of isometric abdominal contractions of varying levels, during which TMS was applied to the primary motor cortex. The evoked twitches were measured as torque, while simultaneous surface electromyographic (EMG) activity was recorded bilaterally from rectus abdominis, erector spinae, tensor fasciae latae, and rectus femoris. VA was calculated as: (1 – superimposed twitch amplitude/estimated resting twitch amplitude) x 100. Estimated resting twitch amplitude was calculated by extrapolation using linear regression of superimposed twitch amplitude against torque for contraction strengths 50–100 % maximum voluntary contraction (MVC).

Results

There was a strong linear relationship between voluntary torque of 50–100 % MVC and TMS-evoked twitch amplitude (r² = 0.994, p = 0.035), and voluntary torque between 50–100 % MVC and VA (r² = 0.997, p = 0.025). VA at a target torque of 100 % MVC was less than 100 % (86.20 ± 2.29 %).

Conclusions

VA of abdominal muscles can be assessed with twitch interpolation using TMS. VA has been shown to be submaximal during maximum voluntary contractions, and it has been demonstrated that superimposed twitch amplitude decreases in a linear fashion with increasing contraction intensity. Using this technique to explore trunk muscle function could help to improve understanding of the neurophysiology of trunk control, including the sites on any deficit in drive and also improve monitoring of the efficacy of treatment regimes for clinical conditions associated with dysfunctions in trunk control e.g. low back pain.

背景：经颅磁刺激（TMS）已被用于评估肢体和背部肌肉的自愿激活（VA），但其评估腹肌VA的能力尚不清楚。使用TMS评估腹肌VA可应用于躯干功能障碍患者，从而进一步了解躯干控制的神经生理学，为实践提供信息，并使康复方案的制定和监测成为可能。目的：本研究的目的是探讨使用经颅磁刺激和抽搐插值技术来测量腹部肌肉的随意激活。方法：20名健康参与者进行了不同程度的腹部收缩，在此期间，TMS应用于初级运动皮层。诱发抽搐以扭矩测量，同时记录双侧腹直肌、竖脊肌、阔筋膜张肌和股直肌的肌表面电图活动。VA计算为：（1 -叠加抽搐振幅/估计静息抽搐振幅）× 100。估计静息抽搐振幅通过外推法计算，使用叠加抽搐振幅与收缩强度50- 100%最大自愿收缩（MVC）扭矩的线性回归。结果：50- 100% MVC的自主转矩与tms诱发的抽搐幅度呈较强的线性关系（r2 = 0.994, p = 0.035）， 50- 100% MVC与VA的自主转矩呈较强的线性关系（r2 = 0.997, p = 0.025）。在目标扭矩为100% MVC时，VA小于100%（86.20±2.29%）。结论：经颅磁刺激可应用抽搐插值法评估腹肌VA。在最大自主收缩期间，VA已被证明是次极大的，并且已被证明，随着收缩强度的增加，叠加抽搐幅度呈线性递减。使用这项技术来探索躯干肌肉功能可以帮助我们更好地理解躯干控制的神经生理学，包括驱动缺陷的部位，也可以改善对与躯干控制功能障碍（如腰痛）相关的临床疾病治疗方案疗效的监测。

{"title":"Measurement of voluntary activation of abdominal flexors using transcranial magnetic stimulation","authors":"Olivia Szepietowski , Hanne Ertman , Shin-Yi Chiou , Paul H. Strutton","doi":"10.1016/j.jelekin.2024.102961","DOIUrl":"10.1016/j.jelekin.2024.102961","url":null,"abstract":"<div><h3>Background</h3><div>Transcranial magnetic stimulation (TMS) has been used to assess voluntary activation (VA) of limb and back muscles, however its ability to assess abdominal muscle VA is unknown. The assessment of abdominal muscle VA using TMS could be applied to patients with trunk dysfunction to enable further understanding of the neurophysiology of trunk control, inform practice and enable the development and monitoring of rehabilitation programmes.</div></div><div><h3>Aim</h3><div>The aim of this study was to investigate use of TMS and the twitch interpolation technique to measure voluntary activation of abdominal muscles.</div></div><div><h3>Methods</h3><div>Twenty healthy participants performed sets of isometric abdominal contractions of varying levels, during which TMS was applied to the primary motor cortex. The evoked twitches were measured as torque, while simultaneous surface electromyographic (EMG) activity was recorded bilaterally from rectus abdominis, erector spinae, tensor fasciae latae, and rectus femoris. VA was calculated as: (1 – superimposed twitch amplitude/estimated resting twitch amplitude) x 100. Estimated resting twitch amplitude was calculated by extrapolation using linear regression of superimposed twitch amplitude against torque for contraction strengths 50–100 % maximum voluntary contraction (MVC).</div></div><div><h3>Results</h3><div>There was a strong linear relationship between voluntary torque of 50–100 % MVC and TMS-evoked twitch amplitude (<em>r</em><sup>2</sup> = 0.994, p = 0.035), and voluntary torque between 50–100 % MVC and VA (<em>r</em><sup>2</sup> = 0.997, p = 0.025). VA at a target torque of 100 % MVC was less than 100 % (86.20 ± 2.29 %).</div></div><div><h3>Conclusions</h3><div>VA of abdominal muscles can be assessed with twitch interpolation using TMS. VA has been shown to be submaximal during maximum voluntary contractions, and it has been demonstrated that superimposed twitch amplitude decreases in a linear fashion with increasing contraction intensity. Using this technique to explore trunk muscle function could help to improve understanding of the neurophysiology of trunk control, including the sites on any deficit in drive and also improve monitoring of the efficacy of treatment regimes for clinical conditions associated with dysfunctions in trunk control e.g. low back pain.</div></div>","PeriodicalId":56123,"journal":{"name":"Journal of Electromyography and Kinesiology","volume":"80 ","pages":"Article 102961"},"PeriodicalIF":2.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142787805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Flexor hallucis longus and tibialis anterior: A synergistic relationship 拇长屈肌和胫骨前肌：一种协同关系。

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-01 DOI: 10.1016/j.jelekin.2024.102966

Jacob Fanous , Charles L. Rice

Flexor hallucis longus (FHL) is an important muscle of the foot and ankle during locomotion, contributing to hallux and plantar flexion. For optimal hallux flexion the ankle needs to be stabilized against plantar flexion which may require action of the dorsiflexors. Due to the deep location of the FHL contractile drive assessed by electromyography (EMG) has not been explored systematically. Thus, the purpose was to test the relationship between the FHL and tibialis anterior (TA), the main dorsiflexor. Using indwelling EMG during isometric maximal voluntary contractions (MVC) of hallux and ankle joint actions, 10 participants (3-females, 7-males) aged 23 ± 1.4 years were tested in custom hallux-flexion and ankle dynamometers, with bipolar wire electrodes recording from the FHL, soleus and TA muscles. During MVC, forces were 169.2 ± 28.5 N, 285.5 ± 65.4 N, and 712.3 ± 313.8 N for hallux flexion, dorsiflexion, and plantar flexion, respectively. During maximal hallux flexion, TA EMG was 53 % (±26.5) of its maximum with negligible soleus activity, 4.7 % (±3.1). No significant correlations were found between TA activity and strength, foot characteristics, sex, height, weight, or soleus activity. This higher level of relative EMG recorded from the TA during maximal hallux flexion has not been observed in prior studies during walking and indicates that the relationship between the FHL and TA is task dependent, thus highlighting the important synergistic role of the TA in allowing optimal toe flexion.

拇长屈（Flexor hallucis longus，FHL）是足部和踝关节在运动过程中的重要肌肉，有助于踝关节的外翻和跖屈。为了达到最佳的踝关节屈曲，需要稳定踝关节以防止跖屈，这可能需要背屈肌的作用。由于 FHL 的位置较深，通过肌电图（EMG）评估的收缩驱动力尚未得到系统的研究。因此，我们的目的是测试 FHL 与主要背屈肌--胫骨前肌（TA）之间的关系。10 名年龄为 23 ± 1.4 岁的参与者（3 名女性，7 名男性）在定制的拇指屈伸和踝关节测力计上进行了测试，使用双极导线电极记录了腓肠肌、比目鱼肌和胫骨前肌在等长最大自主收缩（MVC）时的肌电图。在 MVC 期间，踝关节屈曲、背屈和跖屈的力量分别为 169.2 ± 28.5 N、285.5 ± 65.4 N 和 712.3 ± 313.8 N。在最大拇指屈曲时，TA 肌电图为其最大值的 53 %（±26.5），比目鱼肌活动为 4.7 %（±3.1），可以忽略不计。没有发现TA活动与力量、足部特征、性别、身高、体重或比目鱼肌活动之间有明显的相关性。在以往的研究中，并未观察到在行走过程中最大限度地屈曲拇指时，TA 肌电图记录到更高水平的相对肌电图，这表明腓肠肌和 TA 肌电图之间的关系取决于任务，从而突出了 TA 肌电图在使趾屈曲达到最佳状态方面的重要协同作用。

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引用次数: 0

Reliability of reflex measurements and perceived instability following cutaneous stimulation during gait 步态中皮肤刺激后反射测量的可靠性和感知不稳定性。

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-01 DOI: 10.1016/j.jelekin.2024.102958

Annalee M.H. Friedman , Leif P. Madsen

Individuals with chronic ankle instability (CAI) exhibit a variety of sensorimotor deficits which contribute to long-term health risks and lower overall health-related quality of life. Recent literature finds abnormal cutaneous reflex characteristics and perceptions of instability during gait among those with CAI. These may serve as important patient-specific outcome measures in diagnosing and monitoring the condition, however, the test–retest reliability of these measurements is still undetermined. Therefore, the purpose of this study is to assess reliability of cutaneous reflex amplitudes and variability and perceived instability following perturbation in those with CAI and healthy controls during gait. Subjects walked on a treadmill while receiving random, non-noxious sural nerve stimulations throughout the stance phases of gait. Muscle activity was measured via electromyography for the peroneus longus, and medial and lateral gastrocnemius. Subjects reported their perceived instability following each stimulation. Cutaneous reflex amplitudes and perceived instability throughout the stance phases of gait can be reliably measured within the same day and over a 1-week period while reflex variability may be a less reliable measure. Our findings support the use of these variables as clinical outcome measures to identify and monitor neuromuscular recovery.

慢性踝关节不稳定（CAI）患者表现出各种感觉运动缺陷，这导致长期健康风险和整体健康相关生活质量降低。最近的文献发现异常的皮肤反射特征和知觉不稳定的步态与CAI。这些可能作为诊断和监测病情的重要的患者特异性结果测量，然而，这些测量的重测可靠性仍未确定。因此，本研究的目的是评估CAI患者和健康对照者在步态中扰动后皮肤反射振幅、变异性和感知不稳定性的可靠性。受试者在跑步机上行走，同时在步态的站立阶段接受随机的、无害的腓肠神经刺激。通过肌电图测量腓骨长肌、内侧和外侧腓骨肌的肌肉活动。受试者报告了每次刺激后他们感知到的不稳定性。皮肤反射振幅和整个步态站立阶段的不稳定性可以在同一天和一周内可靠地测量，而反射变异性可能是一个不太可靠的测量。我们的研究结果支持使用这些变量作为临床结果指标来识别和监测神经肌肉恢复。

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引用次数: 0

The unprecedented progresses in neuromechanics over the past 50 years – In celebration of the 50th anniversary of the international society of biomechanics 50年来神经力学的空前进步——庆祝国际生物力学学会成立50周年。

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-01 DOI: 10.1016/j.jelekin.2024.102963

Daniel Hahn, Catherine Disselhorst-Klug, Deborah Falla, Dario Farina

引用次数: 0

Episiotomy and innervation zones of the external anal Sphincter: A case series investigating the impact on neurological patterns 会阴切开术和外肛门括约肌的神经支配区：一个研究对神经模式影响的病例系列。

IF 2 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-02-01 DOI: 10.1016/j.jelekin.2024.102970

Kristina Drusany Starič , Gregor Norčič , Giorgia Campo , Rosario Emanuele Carlo Distefano

Objective

To investigate the impact of mediolateral episiotomy on the innervation zones of the External Anal Sphincter (EAS) in the absence and presence of direct muscular injury.

Methods

This case series examined four primiparous women, including three who underwent vaginal deliveries with mediolateral episiotomy and one cesarean section case for reference. Pre- and post-delivery assessments utilized surface electromyography (sEMG) and endoanal ultrasound to evaluate changes in the EAS’s innervation zones and obstetrical EAS injuries, alongside the Wexner score for fecal incontinence.

Results

Mediolateral episiotomy can alter the innervation pattern of the EAS, with a significant reduction in innervation zones observed in the episiotomy cases compared to the reference cesarean section case. This alteration was evident even in the absence of visible EAS injury, suggesting episiotomy’s potential to disrupt EAS functionality. Notably, the Wexner score indicated varying degrees of fecal incontinence among the episiotomy cases.

Conclusion

Mediolateral episiotomy may impact the EAS’s innervation pattern, highlighting the importance of considering individual innervation zones in episiotomy planning. While the integration of sEMG into routine clinical practice is still evolving, this study underscores its potential as an additional tool for assessing neural integrity, particularly in cases of anal sphincter injury and reconstruction. Future research should explore the dynamics of re-innervation and the correlation between vascular injury and reduced innervation zones to enhance patient-specific care in pelvic floor dysfunction.

目的：探讨外阴中外侧切开术对肛门外括约肌（EAS）神经支配区的影响。方法：本病例系列分析了4例初产妇女，其中3例阴道分娩伴会阴中外侧切开，1例剖宫产，以供参考。产前和产后评估利用表面肌电图（sEMG）和肛管超声来评估EAS的神经支配区变化和产科EAS损伤，以及Wexner评分来评估大便失禁。结果：外阴中外侧切开术可改变EAS的神经支配模式，与参考剖宫产手术相比，外阴切开术患者的神经支配区明显减少。即使没有可见的EAS损伤，这种改变也很明显，这表明会阴切开术可能会破坏EAS功能。值得注意的是，Wexner评分显示会阴切开术患者存在不同程度的大便失禁。结论：外阴中外侧切开术可能影响外阴神经支配模式，强调在外阴切开术计划中考虑单个神经支配区域的重要性。虽然将肌电图纳入常规临床实践仍在不断发展，但本研究强调了其作为评估神经完整性的额外工具的潜力，特别是在肛门括约肌损伤和重建的情况下。未来的研究应探索再神经支配的动力学以及血管损伤与神经支配区减少的相关性，以加强盆底功能障碍的患者特异性护理。

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引用次数: 0