Meichtry André, Romkes Jacqueline, Gobelet Charles, Brunner Reinald, Müller Roland
Unit of Movement Analysis, Clinique romande de rédaptation, SUVA Care, Av. Gd. Champsec 90, 1950 Sion, Switzerland.
Gait Posture. 2007 Jan;25(1):25-32. doi: 10.1016/j.gaitpost.2005.12.016. Epub 2006 Feb 14.
Evaluative quantification of gait disorder minimizing time-consuming and cost-intensive laboratory installations remains a challenging task in movement analysis. We examined the criterion validity of global gait mechanics assessed by trunk accelerometry. Eight female and four male volunteer subjects (mean age, 27.5 years; S.D., 5.1 years; weight, 68.7+/-11.3kg; height, 1.74+/-0.08m) without gait dysfunction participated in the study. They walked barefoot over two adjacent force-platforms at self-selected speeds. In addition to ground reaction forces, vertical, anterior-posterior and medio-lateral accelerations of the trunk were simultaneously measured by means of a light tri-axial accelerometer. Mean acceleration cycles of the trunk and the body centre of mass were calculated. Acceleration vectors were integrated twice to obtain velocity and displacement vectors of the trunk and the centre of mass, respectively. Temporal boundaries of right and left functional stance phases were defined by the two intermediate moments between maximum anterior-posterior velocity and minimal vertical displacement. Cross-correlations of the kinematics of the trunk and the centre of mass were determined. External work and corresponding symmetry indicators were computed for both methods. Centre of mass anterior-posterior displacement lagged behind the trunk by 3.5% of the gait cycle. External power correlated highly (r>0.82) between the trunk model and the centre of mass. Work correlated moderately high (r=0.77) between the two methods. Work and power asymmetry indexes correlated moderately high (r>0.64). Our findings suggest that accelerometry has the potential to assess functional kinematics and energy-related outcomes in large cohorts.
在运动分析中，对步态障碍进行评估量化，同时尽量减少耗时且成本高昂的实验室设备，仍然是一项具有挑战性的任务。我们研究了通过躯干加速度测量评估的整体步态力学的标准效度。八名女性和四名男性志愿者受试者（平均年龄27.5岁；标准差5.1岁；体重68.7±11.3kg；身高1.74±0.08m），无步态功能障碍，参与了该研究。他们以自选速度赤脚走过两个相邻的测力平台。除了地面反作用力外，还通过一个轻型三轴加速度计同时测量躯干的垂直、前后和内外侧加速度。计算躯干和身体质心的平均加速度周期。加速度矢量分别积分两次，以获得躯干和质心的速度和位移矢量。左右功能支撑相的时间边界由前后速度最大值和垂直位移最小值之间的两个中间时刻定义。确定躯干和质心运动学的互相关性。计算两种方法的外部功和相应的对称指标。质心前后位移比躯干滞后步态周期的3.5%。躯干模型和质心之间的外部功率高度相关（r>0.82）。两种方法之间的功中度相关（r=0.77）。功和功率不对称指数中度相关（r>0.64）。我们的研究结果表明，加速度测量有潜力在大量人群中评估功能运动学和与能量相关的结果。
