Kinematic determinants of human locomotion
Kinematic determinants of human locomotion
复制标题
DOI：
10.1113/jphysiol.1996.sp021539
复制
发表时间：
1996-08-01
影响因子：
5.5
通讯作者：
Lacquaniti, F
中科院分区：
文献类型：
--
作者：
Borghese, NA;Bianchi, L;Lacquaniti, F
1. 这项研究的目的是找到在正常运动速度范围内不变的运动学模式。受试者以自由选择的0.9 ~ 2.1 m s（-1）的速度行走，同时在三维空间中记录身体右侧的运动力和地面反作用力。髋部和踝关节屈伸解剖角度的时间过程不仅在不同受试者之间是不同的，甚至在同一受试者的不同试验中也是不同的。相比之下，各肢节（骨盆、大腿、小腿和足）相对于垂直方向的仰角变化的时间过程在受试者中是定型的。为了比较不同速度下的波形，数据按时间相对于步态周期持续时间进行缩放。地面反作用力的模式高度依赖于速度。在髋部和踝关节的屈伸角度中可以识别出几个不同的曲线家族。相反，肢体的总长度和仰角、肢体各节段仰角和膝关节屈伸的波形随速度不变。当所有速度的步态轨迹绘制在由肢体段仰角定义的位置空间中时，它们在平面上描述规则的环路。用主成分分析方法量化了这些角协变的统计特征。前两个主成分合计占实验总方差的约99%，在所有被试中具有数量可比性。这种仰角平面共变的约束与先前描述的姿态控制密切相关。节段间协调规律的存在，与姿势和运动的控制是共同的，可能保证了前进过程中动态平衡的维持，以及通过全身协调的运动协同作用对潜在不稳定因素的预期适应。
1. The aim of this study was to find kinematic patterns that are invariant across the normal range of locomotion speeds. Subjects walked at different, freely chosen speeds ranging from 0.9 to 2.1 m s(-1), while motion and ground reaction forces on the right side of the body were recorded in three-dimensional space.2. The time course of the anatomical angles of flexion-extension at the hip and ankle was variable not only across subjects, but even from trial to trial in the same subject. By contrast, the time course of the changes in the angles of elevation of each limb segment (pelvis, thigh, shank and foot) relative to the vertical was stereotyped across subjects.3. To compare the waveforms across speeds, data were scaled in time relative to gait cycle duration. The pattern of ground reaction forces was highly speed dependent. Several distinct families of curves could be recognized in the flexion-extension angles at the hip and ankle. Instead, the waveforms of global length and elevation of the limb, elevation angles of all limb segments and flexion-extension at the knee were invariant with speed.4. When gait trajectories at all speeds are plotted in the position space defined by the elevation angles of the limb segments, they describe regular loops on a plane. The statistical characteristics of these angular covariations were quantified by means of principal component analysis. The first two principal components accounted together for > 99% of the total experimental variance, and were quantitatively comparable in all subjects.5. This constraint of planar covariation of the elevation angles is closely reminiscent of that previously described for the control of posture. The existence of laws of intersegmental co-ordination, common to the control of posture and locomotion, presumably assures the maintenance of dynamic equilibrium during forward progression, and the anticipatory adaptation to potentially destabilizing factors by means of co-ordinated kinematic synergies of the whole body.