University of Virginia, Exercise and Sports Injury Lab, 210 Emmet Street South, Charlottesville, VA 22904-4407, USA.
Texas State University, Biomechanics/Sports Medicine Lab, 601 University Drive, San Marcos, TX 78666-4616, USA.
Clin Biomech (Bristol). 2020 Mar;73:140-148. doi: 10.1016/j.clinbiomech.2020.01.013. Epub 2020 Jan 20.
Patients with chronic ankle instability often present with altered gait mechanics compared to ankle sprain copers. There is increasing evidence to suggest proximal neuromuscular alterations contribute to the injury etiology, however little is known about how these changes manifest during gait. The purpose of this study was to investigate ipsilateral gluteus maximus and medius functional activity ratios throughout treadmill walking at three speeds (preferred, 120% preferred, and 1.35 m per second) in chronic ankle instability patients compared to copers.
28 females (14 chronic ankle instability, 14 copers) walked at the three gait speeds in randomized order. Ground reaction forces and 10-s gluteal ultrasound clips were simultaneously recorded. Clips were reduced using ground reaction forces to extract 55 measurement frames. Normalized gluteal thickness measures were used to determine functional activity ratios. 2 × 3 analyses of variance were run to assess group and speed effects on gluteal outcomes throughout walking using statistical parametric mapping. Post-hoc t-tests, mean differences, and Cohen's d effect sizes were assessed for significant findings (P ≤ .05).
The chronic ankle instability group had significantly decreased gluteus medius activity throughout the entire gait cycle when compared to the coper group, independent of gait speed (P < .001, mean differences: 0.10-0.18; d: 1.00-3.17). There were no significant group or speed main effects, nor an interaction for gluteus maximus activity.
Gluteal dysfunction throughout walking was identified in chronic ankle instability. The coper group remained within healthy reference muscle activity ranges, suggesting that proximal muscle activation alterations are associated chronic ankle impairments.
与踝关节扭伤适应者相比，慢性踝关节不稳定患者通常表现出不同的步态力学。越来越多的证据表明，近端神经肌肉改变有助于损伤病因，但对于这些变化如何在步态中表现知之甚少。本研究的目的是比较慢性踝关节不稳定患者和适应者在三种速度（首选、首选的 120%和 1.35 米/秒）的跑步机行走过程中，同侧臀大肌和臀中肌功能活动比率。
28 名女性（14 名慢性踝关节不稳定患者，14 名适应者）以随机顺序在三种步态速度下行走。同时记录地面反作用力和 10 秒臀肌超声片段。使用地面反作用力减少片段，以提取 55 个测量帧。使用归一化臀肌厚度测量值来确定功能活动比率。使用统计参数映射，通过 2×3 方差分析评估组间和速度对行走过程中臀肌结果的影响。对有显著意义的发现（P≤.05）进行事后 t 检验、均值差异和 Cohen's d 效应大小评估。
与适应者相比，慢性踝关节不稳定组在整个步态周期中臀中肌活动明显减少，与步态速度无关（P<0.001，平均差异：0.10-0.18；d：1.00-3.17）。臀大肌活动没有显著的组间或速度主效应，也没有交互作用。
在慢性踝关节不稳定中发现了整个行走过程中的臀肌功能障碍。适应者组仍处于健康参考肌肉活动范围内，表明近端肌肉激活改变与慢性踝关节损伤有关。
