Lu Chiahao, Amundsen Huffmaster Sommer L, Harvey Jack C, MacKinnon Colum D
Movement Disorders Laboratory, Department of Neurology, University of Minnesota, 516, 717 Delaware St. SE, Minneapolis, MN 55414, USA.
Movement Disorders Laboratory, Department of Neurology, University of Minnesota, 516, 717 Delaware St. SE, Minneapolis, MN 55414, USA.
Gait Posture. 2017 Sep;57:182-187. doi: 10.1016/j.gaitpost.2017.06.010. Epub 2017 Jun 16.
Gait initiation involves a complex sequence of anticipatory postural adjustments (APAs) during the transition from steady state standing to forward locomotion. APAs have four core components that function to accelerate the center of mass forwards and towards the initial single-support stance limb. These components include loading of the initial step leg, unloading of the initial stance leg, and excursion of the center of pressure in the posterior and lateral (towards the stepping leg) directions. This study examined the incidence, magnitude, and timing of these components and how they change across the lifespan (ages 20-79). 157 individuals performed five trials of self-paced, non-cued gait initiation on an instrumented walkway. At least one component of the APA was absent in 24% of all trials. The component most commonly absent was loading of the initial step leg (absent in 10% of all trials in isolation, absent in 10% of trials in conjunction with another missing component). Trials missing all four components were rare (1%) and were observed in both younger and older adults. There was no significant difference across decades in the incidence of trials without an APA, the number or type of APA components absent, or the magnitude or timing of the APA components. These data demonstrate that one or more components of the APA sequence are commonly absent in the general population and the spatiotemporal profile of the APA does not markedly change with ageing.
步态起始涉及从稳态站立过渡到向前行走过程中一系列复杂的预期姿势调整（APAs）。APAs有四个核心组成部分，其作用是使重心向前并朝向初始单支撑 stance 肢体加速。这些组成部分包括初始步幅腿的加载、初始 stance 腿的卸载以及压力中心在向后和侧向（朝向迈步腿）方向的偏移。本研究考察了这些组成部分的发生率、幅度和时间，以及它们在整个生命周期（20 - 79岁）中的变化情况。157名个体在一条仪器化的走道上进行了五次自定步速、无提示的步态起始试验。在所有试验中，24% 的试验至少缺少一个 APA 组成部分。最常缺失的组成部分是初始步幅腿的加载（单独在所有试验中的10% 中缺失，与另一个缺失组成部分同时出现时在10% 的试验中缺失）。所有四个组成部分都缺失的试验很少见（1%），在年轻人和老年人中均有观察到。在没有 APA 的试验发生率、缺失的 APA 组成部分的数量或类型，以及 APA 组成部分的幅度或时间方面，几十年间没有显著差异。这些数据表明，在普通人群中，APA 序列的一个或多个组成部分通常会缺失，并且 APA 的时空特征不会随着年龄增长而显著变化。
