Ota Susumu, Ogawa Yukari, Ota Hiroki, Fujiwara Tomoya, Sugiyama Tadashi, Ochi Akira
Department of Rehabilitation and Care, Seijoh University, Tokai, Japan.
Department of Physical Medicine and Rehabilitation, Nagoya Tokushukai General Hospital, Kasugai, Japan.
PLoS One. 2017 Jun 22;12(6):e0179260. doi: 10.1371/journal.pone.0179260. eCollection 2017.
The knee adduction moment (KAM) relates to medial knee osteoarthritis (OA). Several gait modifications to reduce the KAM for the prevention of knee OA have been studied. Most of the modifications, however, involve voluntary changes in leg alignment. Here we investigated the biomechanical effects for reducing the KAM of a walking style with a small trunk rotation and arm swing gait, which is a natural walking style used while wearing a kimono (Nanba walk) that shifts the ground reaction force toward the stance leg (reduced lever arm). Twenty-nine healthy adults (21.5 ± 0.6 years) participated in the present study. A three-dimensional analysis system with 10 cameras and 1 force plate was used to obtain the KAM and other biomechanical data. Surface electromyography (EMG) of the hip and trunk muscles (internal obliquus abdominal muscle: IO, external obliquus abdominal muscle: EO, multifidus muscle: MF, and gluteus medius muscle: Gmed) was also assessed, and integrated EMG (iEMG) of the four muscles was assessed in the first and second halves of the stance phase. The 1st and 2nd peak KAMs were significantly decreased during Nanba walking (0.40±0.09 and 0.37±0.13 Nm/kg) compared with normal walking (0.45±0.09 and 0.45±0.13 Nm/kg; P = 0.002, P<0.001, respectively). The lever arm lengths at the 1st and 2nd peak KAMs were also significantly decreased during Nanba walking compared with normal walking (p = 0.023 and p<0.001, respectively). The iEMGs of IO, EO and Gmed muscles during the first half, and the iEMGs of EO and GM during the second half of the stance phase were significantly increased during Nanba walking compared with normal walking. The Nanba gait modification could be a useful strategy for reducing the KAM with high activation of the trunk and hip joint muscles for the prevention and/or treatment of medial knee OA.
膝关节内收力矩（KAM）与膝关节内侧骨关节炎（OA）相关。为预防膝关节OA，人们研究了多种可降低KAM的步态改变方法。然而，大多数改变都涉及腿部对线的自主改变。在此，我们研究了一种小幅度躯干旋转和摆臂步态（即穿着和服行走时的自然步态，南波步）对降低KAM的生物力学效应，这种步态会使地面反作用力向支撑腿转移（杠杆臂缩短）。29名健康成年人（21.5±0.6岁）参与了本研究。使用一个配备10台摄像机和1块测力板的三维分析系统来获取KAM及其他生物力学数据。还评估了髋部和躯干肌肉的表面肌电图（EMG）（腹内斜肌：IO、腹外斜肌：EO、多裂肌：MF和臀中肌：Gmed），并在站立相的前半段和后半段评估了这四块肌肉的积分肌电图（iEMG）。与正常行走（0.45±0.09和0.45±0.13 Nm/kg）相比，南波步行走时第一和第二峰值KAM显著降低（0.40±0.09和0.37±0.13 Nm/kg；P = 0.002，P<0.001）。与正常行走相比，南波步行走时第一和第二峰值KAM处的杠杆臂长度也显著缩短（分别为p = 0.023和p<0.001）。与正常行走相比，南波步行走时站立相前半段IO、EO和Gmed肌肉的iEMG以及后半段EO和GM肌肉的iEMG显著增加。南波步步态改变可能是一种有用的策略，通过高激活躯干和髋关节肌肉来降低KAM，以预防和/或治疗膝关节内侧OA。
