Institute of Physical Activity and Sport Sciences, Cruzeiro do Sul University, São Paulo, SP, Brazil.
Department of Kinesiology, University of Massachusetts, Amherst, MA, USA.
Hum Mov Sci. 2019 Dec;68:102522. doi: 10.1016/j.humov.2019.102522. Epub 2019 Nov 8.
Individuals with stroke often present functional impairment and gait alteration. Among different aspects, intralimb coordination of these individuals is one of the key points that should be considered before implementing any gait intervention protocol. The purpose of this study was to investigate the effects of stroke on intralimb gait coordination of the lower limbs using a vector coding technique. Twenty-five individuals with stroke and 18 non-disabled individuals (control), between 46 and 71 years old, participated in this study. A computerized analysis system registered data from reflective markers placed on specific body landmarks to define thigh, shank, and foot of both body sides, as participants walked at self-selected comfortable speed. Coordination modes, such as in-phase, anti-phase, proximal-segment-phase, and distal-segment-phase, and variability of thigh-shank, and shank-foot were analyzed for the paretic, non-paretic and control limbs during the stance and swing periods, and the entire gait cycle using the vector coding technique. During the stance period, individuals with stroke presented higher frequency of thigh-phase and lower frequency of shank-phase for the thigh-shank coupling and higher frequency of shank-phase for the shank-foot coupling compared to non-disabled controls, indicating that the proximal segment of each pair leads the movement. During the swing period, the paretic limb presented higher frequency for in-phase than non-paretic and control limbs for the thigh-shank coupling. Adaptations in the non-paretic limb were observed in the swing period, with higher frequency than paretic and control limbs in the thigh-phase for the thigh-shank coupling, and higher frequency than the paretic limb in the foot-phase for the shank-foot coupling. No differences in coordination variability were found between paretic, non-paretic, and control limbs. The vector coding technique constitutes a useful tool for identifying gait alterations in intralimb coordination of individuals with stroke. Our coordination results demonstrate a shift from distal to more proximal control during the stance phase in both legs for the individuals with stroke and an inability to decouple segment coordination during the swing phase in the paretic limb. The results indicate that it is more suitable to consider the stance and swing periods separately instead of considering the entire gait cycle to investigate intralimb gait coordination of individuals with stroke.
个体发生脑卒中后常出现功能障碍和步态改变。在不同的方面，脑卒中患者的肢体间协调是实施任何步态干预方案前需要考虑的关键点之一。本研究旨在使用向量编码技术探讨脑卒中对下肢肢体间步态协调的影响。25 名脑卒中患者和 18 名非残疾个体（对照组）参与了本研究，年龄在 46 至 71 岁之间。参与者以自身舒适速度行走时，计算机分析系统会记录放置在特定身体标志点上的反射标记物的数据，以定义双侧大腿、小腿和足部。在站立和摆动期以及整个步态周期中，使用向量编码技术分析了正常和患侧肢体的协同模式，如同相、反相、近端节段相和远端节段相，以及大腿-小腿和小腿-足部的变异性。在站立期，与非残疾对照组相比，脑卒中患者的大腿-小腿耦合中大腿相位的频率更高，小腿相位的频率更低，小腿-足部耦合中小腿相位的频率更高，这表明每对肢体的近端节段先运动。在摆动期，与非患侧和对照组相比，患侧肢体的大腿-小腿耦合中同相的频率更高。在摆动期，非患侧肢体也发生了适应性改变，与患侧和对照组相比，大腿-小腿耦合中大腿相位的频率更高，小腿-足部耦合中足部相位的频率更高。患侧、非患侧和对照组肢体之间的协调变异性没有差异。向量编码技术是一种有用的工具，可用于识别脑卒中患者肢体间协调的步态改变。我们的协调结果表明，脑卒中患者在站立期双腿从远端控制向更近端控制转变，并且在摆动期患侧肢体无法解耦节段协调。结果表明，在研究脑卒中患者的肢体间步态协调时，更适合分别考虑站立期和摆动期，而不是考虑整个步态周期。
