Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA.
Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA.
J Biomech. 2021 Jan 4;114:110135. doi: 10.1016/j.jbiomech.2020.110135. Epub 2020 Nov 22.
The active control of the trunk plays an important role in frontal plane gait stability. We characterized trunk control in response to different step widths using a novel feedback system and examined the different effects of wide and narrow step widths as they each present unique task demands. Twenty healthy young adults walked on a treadmill at 1.25 m/s at five prescribed step widths: 0.33, 1.67, 1, 1.33, 1.67 times preferred step width. Motion capture was used to record trunk kinematics, and surface electromyography was used to record longissimus muscle activation bilaterally. Vector coding was used to analyze coordination between pelvis and thorax segments of the trunk. Results showed that while center of mass only varied across step width in the mediolateral direction, trunk kinematics in all three planes were affected by changes in step width. Angular excursions of the trunk segments increased only with wider widths in the transverse plane. Thorax-pelvis kinematic coordination was affected more by wider widths in transverse plane and by narrower widths in the frontal plane. Peak longissimus activation and bilateral co-activation increased as step widths became narrower. As a control task, walking with varied step widths is not simply a continuum of adjustments from narrow to wide. Rather, narrowing step width and widening step width from the preferred width represent distinct control challenges that are managed in different ways. This study provides foundation for future investigations on the trunk during gait in different populations.
躯干的主动控制在额状面步态稳定性中起着重要作用。我们使用一种新的反馈系统来描述对不同步宽的躯干控制，并检查了宽步和窄步的不同影响，因为它们各自具有独特的任务要求。20 名健康的年轻成年人以 1.25 m/s 的速度在跑步机上行走，步宽分别为 0.33、1.67、1、1.33、1.67 倍的个人偏好步宽。运动捕捉用于记录躯干运动学，表面肌电图用于记录双侧竖脊肌的激活。矢量编码用于分析躯干骨盆和胸廓节段之间的协调。结果表明，虽然质心仅在横向上随步宽变化，但在所有三个平面上，躯干运动学都受到步宽变化的影响。在横断面上，只有在更宽的步宽时，躯干节段的角度偏移才会增加。在横断面上，胸廓-骨盆运动学协调受更宽步宽的影响更大，在额状面上，受更窄步宽的影响更大。随着步宽变窄，竖脊肌的最大激活和双侧协同激活增加。作为对照任务，以不同步宽行走不仅仅是从窄到宽的连续调整。相反，从偏好宽度变窄步宽和变宽步宽代表了不同的控制挑战，需要以不同的方式来管理。本研究为不同人群步态中躯干的进一步研究提供了基础。
