Lower Extremity & Gait Studies Research Group, La Trobe University, Australia; Department of Physiotherapy, La Trobe University, Australia.
Lower Extremity & Gait Studies Research Group, La Trobe University, Australia; Department of Rural Human Biosciences, La Trobe University, Australia.
Gait Posture. 2014 Feb;39(2):822-6. doi: 10.1016/j.gaitpost.2013.11.008. Epub 2013 Nov 17.
Gluteus minimus is believed to consist of two structurally and functionally unique segments (anterior and posterior); however there is a lack of electromyography (EMG) research that attempts to verify current theoretical knowledge of this muscle. The purpose of this study was therefore to evaluate the function of gluteus minimus during gait, and to determine whether anterior and posterior segments are functionally independent. Bipolar fine wire intramuscular EMG electrodes were inserted into anterior and posterior gluteus minimus segments of fifteen healthy volunteers (9 males) according to previously verified guidelines. Participants completed a series of four walking trials, followed by maximum voluntary isometric contractions in five different positions. Temporal and amplitude variables for each segment were compared across the gait cycle with independent t-tests. The relative contribution of each segment to the maximum resisted trials was compared with Mann-Whitney U tests (α = 0.05). Anterior and posterior segments were contracting at different relative intensities for three of the five maximum resisted trials (effect size = 0.39 to 0.62, P < 0.037). The posterior segment was larger in EMG amplitude (peak and average) during the first 20% of the gait cycle (effect size = 0.96 to 1.03, P < 0.02), while the anterior segment peaked later in the stance phase (effect size = 0.83, P = 0.034). Gluteus minimus is therefore composed of functionally independent segments. These results build on contemporary theoretical knowledge and may signify hip stabilising roles for each segment across different phases of the gait cycle.
臀小肌被认为由两个在结构和功能上都独特的部分（前侧和后侧）组成；然而，目前缺乏肌电图（EMG）研究来验证该肌肉的现有理论知识。因此，本研究的目的是评估臀小肌在步态中的功能，并确定前侧和后侧部分是否在功能上是独立的。根据先前验证的指南，将双极细金属丝肌内 EMG 电极插入 15 名健康志愿者（9 名男性）的臀小肌前侧和后侧部分。参与者完成了一系列四项步行试验，然后在五个不同位置进行最大自主等长收缩。通过独立 t 检验比较每个节段在步态周期内的时间和幅度变量。用 Mann-Whitney U 检验（α=0.05）比较每个节段在最大抵抗试验中的相对贡献。前侧和后侧部分在五个最大抵抗试验中的三个试验中以不同的相对强度收缩（效应量=0.39 至 0.62，P<0.037）。在后侧部分在步态周期的前 20%中，EMG 幅度（峰值和平均值）更大（效应量=0.96 至 1.03，P<0.02），而在前侧部分在站立阶段后期达到峰值（效应量=0.83，P=0.034）。因此，臀小肌由功能上独立的部分组成。这些结果建立在当代理论知识的基础上，可能表明每个部分在步态周期的不同阶段都有稳定髋关节的作用。
