Journal of Electromyography and Kinesiology最新文献_第2页

Frequency-specific modulations of oscillatory neural drives to lower leg muscles during gait with aiding and impeding horizontal forces 在辅助和阻碍水平力的步态中，振荡神经驱动对小腿肌肉的频率特异性调节。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-01 DOI: 10.1016/j.jelekin.2025.103098

Ryosuke Kitatani , Rina Numata , Runa Sorimachi , Naofumi Otsuru , Sumiya Shibata , Hideaki Onishi

Gait training with impeding horizontal force around the center of mass (COM) improves gait speed due to enhancements on activities in gastrocnemius (GC) muscles; however, the underlying neural mechanisms of these changes remain unclear. This study aimed to examine the influence of impeding horizontal force around the COM during gait on oscillatory neural drives to lower leg muscles using coherence analysis of paired surface electromyography, which in the alpha and beta bands reflect subcortical and cortical origins, respectively. Twenty healthy young adults participated in three gait conditions: normal gait without additional horizontal force, and gait with aiding and impeding horizontal forces, which were applied with a load of 5 % of body weight at the second sacral spine level via a waist belt. Medialis and lateralis GC intermuscular coherence in the alpha band (7.5–15 Hz) was significantly higher under the impeding force condition compared to the aiding force and normal gait conditions, whereas beta-band (15–35 Hz) coherence was significantly higher in the impeding force condition only compared to the aiding force condition. Impeding horizontal force around the COM during gait enhances oscillatory neural drives, predominantly from subcortical origins to GC muscles, with additional cortical contributions.

围绕质心（COM）的阻碍水平力步态训练由于增强腓肠肌（GC）肌肉的活动而提高了步态速度；然而，这些变化的潜在神经机制尚不清楚。本研究旨在通过对成对的肌电图的相干性分析，研究步态时COM周围的阻碍水平力对下肢肌肉振荡神经驱动的影响，在α和β波段分别反映皮层下和皮层起源。20名健康的年轻人参加了三种步态条件：无额外水平力的正常步态和辅助和阻碍水平力的步态，通过腰带在第二骶棘水平施加5%体重的负荷。阻碍力条件下内侧肌和外侧肌α带（7.5 ~ 15 Hz）的肌间相干性显著高于辅助力和正常步态条件，而阻碍力条件下β带（15 ~ 35 Hz）的肌间相干性仅显著高于辅助力条件。在步态过程中，阻止COM周围的水平力增强了振荡神经驱动，主要是从皮层下起源到GC肌肉，并有额外的皮层贡献。

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引用次数: 0

Real-time changes in rate of torque development and corticospinal excitability during transcutaneous spinal cord stimulation in healthy individuals 健康个体经皮脊髓刺激过程中扭矩发展速率和皮质脊髓兴奋性的实时变化

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-01 DOI: 10.1016/j.jelekin.2025.103096

Keita Takano , Tomofumi Yamaguchi , Kano Kikuma , Yamato Omi , Natsuki Katagiri , Takatsugu Sato , Shigeo Tanabe , Kaoru Honaga , Kunitsugu Kondo , Toshiyuki Fujiwara

Transcutaneous spinal cord stimulation (tSCS) is used to induce neural plasticity and enhance motor function recovery following a stroke. Examining real-time changes under tSCS regulation would provide comprehensive insights into the mechanisms underlying motor functional recovery and neural plasticity. However, the real-time changes in the rate of torque development and neural excitability during tSCS remain unclear. This study explored the real-time changes in the rate of torque development and corticospinal excitability during tSCS. Twenty healthy individuals participated in two separate experiments, each with a tSCS condition and control condition. Under the tSCS condition, tSCS was applied to the Th11–Th12 spinous processes at an intensity twice the sensory threshold of the trunk muscles. The peak rate of torque development in the explosive lower limb extension movement in Experiment 1 and motor-evoked potential (MEP) amplitudes in Experiment 2 were assessed before the intervention and with (tSCS condition) or without tSCS (control). The peak rate of torque development and MEP amplitudes increased during tSCS compared to before tSCS (P = 0.038 and 0.047, respectively). However, the control condition had no significant effect. These findings demonstrate that tSCS enhances the rate of torque development and increases corticospinal excitability in healthy individuals, offering valuable fundamental insights into tSCS mechanisms and potential neurorehabilitation applications.

经皮脊髓刺激（tSCS）用于诱导脑卒中后的神经可塑性和增强运动功能恢复。研究tSCS调控下的实时变化将为运动功能恢复和神经可塑性的机制提供全面的见解。然而，在tSCS期间，扭矩发展速度和神经兴奋性的实时变化尚不清楚。本研究探讨了tSCS过程中扭矩发展速率和皮质脊髓兴奋性的实时变化。20名健康个体参加了两个独立的实验，每个实验都有tSCS条件和对照条件。在tSCS条件下，tSCS以两倍于躯干肌肉感觉阈值的强度作用于Th11-Th12棘突。实验1的爆发性下肢伸展运动的扭矩发展峰值速率和实验2的运动诱发电位（MEP）振幅分别在干预前、tSCS条件下和无tSCS条件下进行评估。与tSCS前相比，tSCS期间扭矩发展峰值速率和MEP振幅均有所增加（P分别为0.038和0.047）。而对照条件无显著影响。这些发现表明，tSCS可以提高健康个体的扭矩发展速度和皮质脊髓兴奋性，为tSCS的机制和潜在的神经康复应用提供了有价值的基础见解。

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引用次数: 0

Characteristics of lower limb skeletal muscle activity during walking in patients with knee osteoarthritis and knee extensor weakness: Comprehensive assessment using positron emission tomography 膝关节骨关节炎和膝关节伸肌无力患者行走时下肢骨骼肌活动的特征：使用正电子发射断层扫描进行综合评估。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-11-14 DOI: 10.1016/j.jelekin.2025.103085

Takuya Sengoku , Takeshi Oshima , Yasushi Takata , Junichi Taki , Yusuke Yanatori , Goro Sakurai , Seigo Kinuya , Satoru Demura , Junsuke Nakase

Purpose

To compare the whole-body muscles glucose metabolism during walking among patients with knee osteoarthritis (KOA) with and without knee extensor weakness using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET).

Methods

Participants were divided into group A (n = 7) with good and group B (n = 15) with poor knee extensor strength, based on a weight-bearing ratio of 0.45 Nm/kg of the knee extensor strength required for walking adaptation. After treadmill walking task, FDG-PET computed tomography was performed, and standardised uptake values of glucose metabolism were calculated. Hip abductor and knee extensor strengths were measured using a handheld dynamometer. A comparison between the two groups and investigation into the correlation between glucose metabolism and muscle strength (hip abductor and knee extensor) were conducted.

Results

No significant differences were observed in overall glucose metabolism; However, when adjusting for sex between the two groups, Group B exhibited higher glucose metabolism in the tibialis anterior muscle (P = 0.04). Furthermore, glucose metabolism in the rectus femoris muscle showed a negative correlation with muscle strength during isometric contractions for hip abductor and knee extensor.

Conclusion

Patients with KOA exhibiting reduced knee extensor strength have increased glucose metabolism in the tibialis anterior.

目的：应用18f -氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）比较伴有和不伴有膝伸肌无力的膝骨性关节炎（KOA）患者行走时全身肌肉葡萄糖代谢。方法：根据步行适应所需膝关节伸肌力量的负重比为0.45 Nm/kg，将参与者分为膝关节伸肌力量较好的A组（n = 7）和膝关节伸肌力量较差的B组（n = 15）。在完成跑步机行走任务后，进行FDG-PET计算机断层扫描，计算葡萄糖代谢的标准化摄取值。髋关节外展肌和膝关节伸肌力量测量使用手持式测功仪。对两组进行比较，并探讨糖代谢与肌肉力量（髋关节外展肌和膝关节伸肌）的相关性。结果：两组总糖代谢无显著差异；然而，当调整两组之间的性别时，B组在胫骨前肌中表现出更高的葡萄糖代谢（P = 0.04）。此外，股直肌的葡萄糖代谢与髋外展肌和膝伸肌等长收缩时的肌肉力量呈负相关。结论：KOA患者表现为膝关节伸肌力量减弱，胫前肌葡萄糖代谢增加。

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引用次数: 0

Do technological tools improve reliability in ankle dorsiflexion assessment? A study across healthy and injured individuals 技术工具能提高踝关节背屈评估的可靠性吗？一项针对健康和受伤个体的研究

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-11-14 DOI: 10.1016/j.jelekin.2025.103087

Germán Cánovas-Ambit , Jorge Godínez Leal , Aitor Baño-Alcaraz , Manuel López Nicolas , José A. García-Vidal

Background

The objective was to examine the intra- and inter-rater reliability of three instruments for measuring ankle dorsiflexion (ADF) range of motion (ROM) and degree of asymmetry in the Weight-Bearing Lunge Test (WBLT). Additionally, the study evaluated the agreement between these tools in both asymptomatic and symptomatic populations.

Methods

Sixty-five participants were included, comprising 32 healthy individuals and 33 subjects presenting ankle pathology. Measurements were conducted on two separate occasions by two independent assessors using distinct methods to quantify ADF-ROM and asymmetry during the WBLT.

Results

Veloflex demonstrated strong intra- and inter-rater reliability, with intraclass correlation coefficients (ICCs) consistently above 0.88, for both ADF-ROM measurement and asymmetry detection across symptomatic and asymptomatic groups. Furthermore, an acceptable agreement was observed between Veloflex and the tape measure in the symptomatic cohort, while agreement between Veloflex and the Dorsiflex app was suboptimal.

Conclusion

The findings indicate that Veloflex is a reliable tool for assessing ADF-ROM and asymmetry in both healthy and pathological cases. While the tape measure offers a viable alternative to Veloflex in symptomatic assessments, substitution of Veloflex with the Dorsiflex app is not supported due to inconsistent agreement.

目的是检查负重弓步试验（WBLT）中测量踝关节背屈（ADF）运动范围（ROM）和不对称程度的三种仪器的内部和内部可靠性。此外，该研究评估了这些工具在无症状和有症状人群中的一致性。方法共纳入65例受试者，其中32例为健康个体，33例为踝关节病变。测量由两个独立的评估人员在两个不同的场合进行，使用不同的方法来量化WBLT期间的ADF-ROM和不对称性。结果veloflex在有症状和无症状组的ADF-ROM测量和不对称性检测中显示出很强的组内和组间可靠性，组内相关系数（ICCs）始终高于0.88。此外，在有症状的队列中，Veloflex和卷尺之间的一致性是可以接受的，而Veloflex和Dorsiflex应用程序之间的一致性是次优的。结论Veloflex是评估ADF-ROM和非对称性的可靠工具，无论在健康还是病理病例中都是如此。虽然卷尺在症状评估中提供了Veloflex的可行替代方案，但由于协议不一致，不支持用Dorsiflex应用程序替代Veloflex。

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引用次数: 0

Optimal path for measurement of biceps femoris long head architecture using synchronized ultrasound and two-dimensional video probe kinematics 利用同步超声和二维视频探针运动学测量股二头肌长头结构的最佳路径

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-11-14 DOI: 10.1016/j.jelekin.2025.103086

Eleftherios Kellis, Georgios Salonikios, Athanasios Ellinoudis

The biceps femoris long head (BF) exhibits complex morphology, with fascicle orientation and aponeurotic curvature varying along its length. In vivo assessment of fascicle length (FL), pennation angle (PA), and muscle thickness (MT) is commonly performed with B-mode ultrasound (US), yet probe placement may confound interpretation of morphological variation. This study examined the effects of probe trajectory on BF architecture by synchronizing conventional B-mode US with two-dimensional kinematic tracking. Nineteen males were scanned in a side-lying position with the hip and knee flexed at 20°. B-mode US scans were performed along three paths: Central (center of the mediolateral width), 10 mm medial, and 10 mm lateral relative to Central. A high-speed camera tracked probe movement, synchronized with the US video. Measurements included FL, PA, and intermediate (IT) and full muscle thickness (MT) at four points along the muscle. Probe path significantly influenced FL and PA but not MT or IT. Medial and lateral scans produced longer fascicles and smaller PAs compared to the central path (p < 0.05). Differences in FL and PA exceeded 10 %, corresponding to ∼7–10 mm in FL and 2–3° in PA. These magnitudes equal or surpass values often attributed to training adaptations or injury-related remodeling. Probe trajectory can bias BF architectural estimates by amounts that rival physiologically meaningful changes, highlighting the need for standardized scanning protocols.

股二头肌长头（BF）表现出复杂的形态，其束状方向和腱膜曲率沿其长度变化。在体内评估肌束长度（FL）、笔尖角（PA）和肌肉厚度（MT）通常是用b超（US）进行的，但探针的放置可能会混淆形态学变化的解释。通过将传统的b模US与二维运动跟踪同步，研究了探针轨迹对BF结构的影响。19名男性采用侧躺姿势，臀部和膝盖弯曲20°进行扫描。B-mode US扫描沿三条路径进行：中央（中外侧宽度的中心），内侧10mm和相对于中央的外侧10mm。高速摄像机跟踪探针的运动，与美国视频同步。测量包括沿肌肉四个点的FL、PA、中间（IT）和全肌厚度（MT）。探针路径对FL和PA有显著影响，但对MT和IT无显著影响。与中央路径相比，内侧和外侧扫描产生更长的肌束和更小的PAs （p < 0.05）。FL和PA的差异超过10%，对应于FL为~ 7-10 mm， PA为2-3°。这些数值等于或超过通常归因于训练适应或损伤相关重塑的数值。探针轨迹可能会对BF架构的估计产生偏差，其数量可能与生理上有意义的变化相匹配，这突出了标准化扫描协议的必要性。

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引用次数: 0

Co-contraction about the ankle increases with the threat of a walking perturbation 踝关节的共同收缩随着行走干扰的威胁而增加

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-11-09 DOI: 10.1016/j.jelekin.2025.103082

Nancy T. Nguyen , James B. Tracy , Jeremy R. Crenshaw

The ability to prevent a fall after a walking perturbation is dependent upon the initial, modifiable conditions related to stability. Individuals may proactively modify their gait to maintain stability by increasing co-contraction about the ankle, increasing the resistance to a perturbing force. The purpose of this study was to investigate whether such proactive ankle co-contraction occurs when walking under the threat of large perturbations. Participants walked on a computer-controlled treadmill under nine randomly ordered task conditions with combinations of three walking speeds and three perturbation conditions. Bilateral EMG of the tibialis anterior and medial gastrocnemius were recorded. Co-contraction indices (CCI) of these muscles during stance prior to a perturbation were calculated. The effects of walking perturbation condition and speed on CCI were assessed using a 3x3 repeated-measures ANOVA. There were no significant interactions of perturbation and speed. There was a significant main effect of perturbation condition, with higher CCI in anterior and posterior perturbations compared to no perturbation. These results suggest that co-contraction occurs in a manner that may increase resistance to perturbations. Future studies will determine the extent to which populations with a high risk of falling are able to proactively modify their gait in anticipation of a perturbation.

行走扰动后防止跌倒的能力取决于与稳定性相关的初始、可修改的条件。个体可能会主动调整步态，通过增加踝关节的共同收缩来保持稳定，增加对干扰力的抵抗力。本研究的目的是调查在大扰动的威胁下行走时是否会发生这种主动踝关节共同收缩。参与者在电脑控制的跑步机上行走，在九种随机排序的任务条件下，分别有三种行走速度和三种干扰条件。记录双侧腓肠肌前、内侧肌肌电图。计算摄动前这些肌肉的共收缩指数（CCI）。采用3 × 3重复测量方差分析评估行走扰动条件和速度对CCI的影响。微扰和速度之间没有显著的相互作用。摄动条件的主效应显著，前后摄动的CCI高于无摄动的CCI。这些结果表明，共收缩的发生方式可能会增加对扰动的抵抗力。未来的研究将确定跌倒风险高的人群能够在多大程度上主动调整他们的步态，以应对干扰。

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引用次数: 0

Effects of peripheral fatigue of ankle evertors on force sense and electromyographic activity in healthy subjects 踝关节外周疲劳对健康受试者力感和肌电活动的影响。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-11-05 DOI: 10.1016/j.jelekin.2025.103083

Tjaž BREZOVAR , Maja VENE , Taja TUČEN , Anika JAGARINEC , Urška PUH , Alan KACIN

Background

Ankle proprioception is essential for dynamic stability, but fatigue may impair force sense and neuromuscular control, increasing injury risk. Their relationship remains unclear. Objective: To examine the effects of ankle evertor fatigue on force sense accuracy and variability, along with associated changes in muscle activation. Methods: Twenty-four healthy participants completed a force-matching task in ankle eversion at 25% and 50% of MVIC before and after a fatigue protocol. Force sense was assessed by constant, absolute, and variable error and coefficient of variation. RMS amplitude was calculated for the peroneus longus, tibialis anterior, soleus, and gastrocnemius medialis, and median frequency only for the peroneus longus. Results: With fatigue, there was a 34.7% reduction in MVIC torque (p < 0.05). During force-matching tasks, variable error at 50% MVIC and coefficient of variation without visual feedback at 25% and 50% MVIC increased (p < 0.01), EMG amplitude of all muscles substantially increased (p < 0.05), and median frequency of the peroneus longus decreased (p < 0.001). Conclusion: Peripheral fatigue of ankle evertors increases variability in muscle force output, which is accompanied by compensatory motor unit recruitment during force matching, resulting in elevated variability.

背景：踝关节本体感觉对动态稳定性至关重要，但疲劳可能损害力感和神经肌肉控制，增加损伤风险。他们的关系尚不清楚。目的：探讨踝关节旋转疲劳对力感准确性和变异性的影响，以及与之相关的肌肉激活变化。方法：24名健康参与者在疲劳方案前后分别以25%和50%的MVIC完成踝关节外翻力匹配任务。力感通过恒定、绝对和可变误差和变异系数进行评估。计算腓骨长肌、胫骨前肌、比目鱼肌和腓肠肌内侧肌的均方根振幅，仅计算腓骨长肌的中位数频率。结果：在疲劳状态下，MVIC扭矩降低34.7% (p)。结论：踝关节外周性疲劳增加了肌肉力量输出的变异性，这伴随着力量匹配过程中代偿运动单位的补充，导致变异性升高。

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引用次数: 0

Automatic detection of swallowing events based on surface electromyography 基于表面肌电图的吞咽事件自动检测

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-11-04 DOI: 10.1016/j.jelekin.2025.103081

Juan Salvador Mercado-Villegas , Juan Rafael Orozco-Arroyave , Andres Orozco-Duque , Sebastian Roldan-Vasco

Clinical evaluation of dysphagia requires modeling different phases of swallowing. This process is expensive, invasive, subjective, and typically based on Videofluoroscopic Swallowing Study (VFSS) studies. This work evaluates the use of surface electromyography (sEMG) signals for detecting bolus passage through the mandible line (ManL) and upper esophageal sphincter (UES) in patients with oropharyngeal dysphagia. The paper introduces a novel method where GRU networks are fed with spectrograms resulting from processing sEMG signals. Using VFSS as the gold standard, our results yielded F1 scores up to 96% for binary, and 80% for tri-class classifications, outperforming state-of-the-art methods. The detection was more accurate with larger volumes and thinner consistencies. These results indicate that sEMG is a promising biosignal especially because of its non-invasiveness nature, making it an ideal complement to VFSS for dysphagia diagnosis and monitoring.

吞咽困难的临床评估需要模拟吞咽的不同阶段。这个过程是昂贵的，侵入性的，主观的，通常是基于视频透视吞咽研究（VFSS）的研究。本研究评估了表面肌电图（sEMG）信号在口咽吞咽困难患者中检测药物通过下颌骨线（ManL）和上食管括约肌（UES）的应用。本文介绍了一种将表面肌电信号处理后的频谱图馈入GRU网络的新方法。使用VFSS作为金标准，我们的结果在二元分类中获得了高达96%的F1分数，在三类分类中获得了80%的F1分数，优于最先进的方法。体积越大，浓度越薄，检测越准确。这些结果表明，肌电图是一种很有前途的生物信号，特别是因为它的非侵入性，使它成为VFSS诊断和监测吞咽困难的理想补充。

引用次数: 0

Bilateral activation failure of ankle dorsiflexors in patients with hip osteoarthritis undergoing total hip arthroplasty 全髋关节置换术中髋关节骨性关节炎患者双侧踝关节背屈肌激活失败。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-11-04 DOI: 10.1016/j.jelekin.2025.103084

Federico Temporiti , Paola Adamo , Francesco Baldracco , Andrea Tarasconi , Davide De Leo , Arianna Colpani , Nicola Maffiuletti , Roberto Gatti

The study aimed at investigating voluntary activation of ankle dorsiflexors in patients with hip osteoarthritis before and after total hip arthroplasty (THA). Twenty-six subjects with unilateral end-stage hip osteoarthritis were assessed for voluntary activation level (VAL) of ankle dorsiflexors of operative and non-operative sides using twitch interpolation technique. Maximal isometric force (MVIC), intrinsic electrically-evoked force (EF) and rate of force development (RFD) at 50 ms, 100 ms and 200 ms during voluntary contractions were also collected. Patients were assessed on the preoperative and third postoperative days and data were compared to 26 age-matched healthy subjects. Patients revealed lower VAL (before surgery: MD 7.7 %, CI₉₅ 0.4, 14.9; after surgery: MD 12.4 %; CI₉₅ 5.5, 19.2), MVIC, EF and RFD than healthy subjects on the operative side. On the nonoperative side, patients revealed lower postoperative VAL than healthy subjects (MD 9.0 %, CI₉₅ 2.4, 15.6) as well as lower evoked force and RFD before and after surgery. Bilateral activation failure of ankle dorsiflexors was found in patients undergoing THA. Such impairments were accompanied by deficits in maximal, evoked and explosive force. These findings confirmed impairments in neuromuscular function of muscles that do not surround the affected joint and may depend on supraspinal pathophysiological mechanisms and learned non-use.

该研究旨在调查髋关节骨性关节炎患者在全髋关节置换术（THA）前后踝关节背屈肌的自主激活。采用抽动插值法对26例单侧终末期髋关节骨性关节炎患者手术侧和非手术侧踝关节背屈肌的自主激活水平（VAL）进行评估。采集自发性收缩时50 ms、100 ms和200 ms时的最大等距力（MVIC）、内在电诱发力（EF）和力发展率（RFD）。术前和术后第三天对患者进行评估，并将数据与26名年龄匹配的健康受试者进行比较。患者术侧VAL（术前：MD 7.7%, CI95 0.4, 14.9；术后：MD 12.4%, CI95 5.5, 19.2）、MVIC、EF、RFD均低于健康者。在非手术侧，患者术后VAL低于健康者（MD为9.0%，CI95为2.4,15.6%），且术前和术后诱发力和RFD均较低。在THA患者中发现双侧踝关节背屈肌激活失败。这些损伤伴随着最大、诱发力和爆发力的缺陷。这些发现证实了不围绕受影响关节的肌肉的神经肌肉功能受损，可能取决于椎上病理生理机制和习得性不使用。

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引用次数: 0

Young and older adult females show increased muscle compensation compared to males while moving an external load for three functional tasks 与男性相比，年轻和年长的成年女性在进行三种功能任务的外部负荷时，肌肉补偿有所增加

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-10-27 DOI: 10.1016/j.jelekin.2025.103078

Zoe M. Moore , Joshua Pataky , Lilla Caton , Mitchell Vanden Heuvel , Sean Furlong , Ashlie Miller , Meghan E. Vidt

Rotator cuff tears (RCT) are common. Prior work studied effects of RCT severity, load, and task on functional performance, but no work has examined the combined effect of factors or age- and sex-based effects, which was the objective of this study. Models representing young/older adult males/females with varying RCT severity were used. Seven external loads were applied to the hand during 3 functional tasks. Multiple 2-way ANOVAs and exploratory mixed effects model were used to determine muscle force differences between RCT severity, external load, sex, age, and task. Root mean squared error (RMSE) was used to quantify hand deviation. The deltoid, pectoralis major, infraspinatus, and teres minor muscles increased force for interactions of RCT severity, external load, age, sex, and task and the following main effects: RCT severity (all p < 0.0043), external load (all p < 0.0001), female sex (all p < 0.0001), age (all p < 0.0214), and multi-planar tasks (all p < 0.0001). Larger force contributions occurred for female/older adults with increased RCT severity/external load. Greatest hand deviation occurred for massive tear severity, 66.7 N load for all model permutations (all RMSE > 0.0077 m), with greater deviation for multi-planar vs planar tasks. Study outcomes aid in development of sex, age, and RCT severity specific rehabilitation that incorporates multi-planar movement.

肩袖撕裂（RCT）是常见的。先前的工作研究了RCT严重程度、负荷和任务对功能表现的影响，但没有工作检查了因素的综合影响或年龄和性别的影响，这是本研究的目的。模型代表不同RCT严重程度的年轻/老年成年男性/女性。在3个功能任务中，手被施加了7个外部负载。采用多重双因素方差分析和探索性混合效应模型来确定RCT严重程度、外负荷、性别、年龄和任务之间的肌力差异。用均方根误差（RMSE）来量化手部偏差。三角肌、胸大肌、冈下肌和小圆肌在RCT严重程度、外部负荷、年龄、性别和任务的相互作用下增加了力量，主要影响如下：RCT严重程度（均p <； 0.0043）、外部负荷（均p <； 0.0001）、女性性别（均p <； 0.0001）、年龄（均p <； 0.0214）和多平面任务（均p <； 0.0001）。在RCT严重程度/外负荷增加的女性/老年人中，力的贡献更大。最大的手偏差发生在大规模撕裂严重程度，所有模型排列的66.7 N负载（所有RMSE >； 0.0077 m），多平面与平面任务的偏差更大。研究结果有助于性别、年龄和RCT严重程度特异性康复的发展，包括多平面运动。

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引用次数: 0