Nakagawa Theresa H, Muniz Thiago B, Baldon Rodrigo M, Maciel Carlos D, Amorim César F, Serrão Fábio V
Physical Therapy Department, Universidade Federal de São Carlos, São Carlos, SP, Brazil.
Rev Bras Fisioter. 2011 Jan-Feb;15(1):59-65. doi: 10.1590/s1413-35552011005000003. Epub 2011 Mar 4.
Proximal factors have been proposed to influence the biomechanics of the patellofemoral joint. A delayed or diminished gluteus medius (GM) activation, before the foot contact on the ground during functional activities could lead to excessive femur adduction and internal rotation and be associated with anterior knee pain (AKP). There are few studies on this topic and the results were inconclusive, therefore, it is necessary to investigate the GM preactivation pattern during functional activities.
To compare the GM electromyographic (EMG) preactivation pattern during walking, descending stairs and in single leg jump task in women with and without AKP.
Nine women clinically diagnosed with AKP and ten control subjects with no history of knee injury participated in this study. We evaluated GM EMG linear envelope before the foot contact on the ground during walking and GM onset time and EMG linear envelope during descending stairs as well as in a single leg vertical jump. Mann-Whitney U tests were used to determine the between-group differences in GM EMG preactivation pattern.
No between-group differences were observed in GM linear envelope during walking (P=0.41), GM onset time and linear envelope during descending stairs (P=0.17 and P=0.15) and single leg jump (P=0.81 and P=0.33).
Women with AKP did not demonstrated altered GM preactivation pattern during functional weight bearing activities. Our results did not support the hypothesis that poor GM preactivation pattern could be associated with AKP.
近端因素被认为会影响髌股关节的生物力学。在功能活动中，足部接触地面之前，臀中肌（GM）激活延迟或减弱可能导致股骨过度内收和内旋，并与前膝痛（AKP）相关。关于这个主题的研究很少，结果也尚无定论，因此，有必要研究功能活动期间GM的预激活模式。
比较有和没有AKP的女性在行走、下楼梯和单腿跳跃任务期间GM的肌电图（EMG）预激活模式。
9名临床诊断为AKP的女性和10名无膝关节损伤史的对照受试者参与了本研究。我们评估了行走过程中足部接触地面之前GM的EMG线性包络，以及下楼梯和单腿垂直跳跃过程中GM的起始时间和EMG线性包络。采用曼-惠特尼U检验来确定GM EMG预激活模式的组间差异。
在行走期间GM线性包络（P=0.41）、下楼梯期间GM起始时间和线性包络（P=0.17和P=0.15）以及单腿跳跃期间（P=0.81和P=0.33），未观察到组间差异。
患有AKP的女性在功能性负重活动期间未表现出GM预激活模式的改变。我们的结果不支持GM预激活模式不佳可能与AKP相关的假设。
