Université Côte d'Azur, LAMESS, Nice, France -
Université Côte d'Azur, LAMESS, Nice, France.
Eur J Phys Rehabil Med. 2018 Jun;54(3):380-387. doi: 10.23736/S1973-9087.17.04722-0. Epub 2017 Aug 29.
Impairments resulting from hemiparetic stroke lead to persistent difficulties with walking. Abnormal co-contraction patterns of lower limb muscles might be a compensatory mechanism to deal with its resulting gait impairments.
The aim of this study was to assess muscle co-contraction obtained from muscle moments in chronic hemiparetic patients presenting a stiff-knee gait (SKG) during walking.
Cross-sectional study.
Clinical movement analysis laboratory in a health center and a community hospital.
Twelve hemiparetic patients 6 months' post-stroke (mean±SD age 49.3±12.5) walking with a SKG and twelve healthy adults (mean±SD age 23.5±7.7).
Hemiparetic patients walked at their natural gait speed while healthy adults walked at their natural and slow gait speed. Spatiotemporal, kinetic and kinematic gait parameters were determined for both lower limbs. Co-Contraction Index at the knee and the ankle was calculated from muscle moments estimated using an EMG-driven model during the first (DS1) and second (DS2) double support and the single support (SS) phases and the swing phase (SW).
The results revealed that chronic stroke patients have reduced ankle co-contraction and increased knee co-contraction during DS1 phase, increased ankle co-contraction during DS2 phase and increased knee co-contraction during SW phase on the paretic side. On the non-paretic side, muscle co-contraction was higher at the knee during SS phase.
Increased co-contraction during walking in both the paretic and the non-paretic side, in patients with hemiparesis exhibiting a SKG, might be an adaptive strategy to increase walking stability, as it may be related to spasticity, but also could result in a high metabolic cost.
The information obtained in this study may be used to support rehabilitation programs focusing on the selectivity of movement control such as strength or power training.
偏瘫引起的损伤会导致行走持续困难。下肢肌肉的异常协同收缩模式可能是应对步态损伤的一种代偿机制。
本研究旨在评估患有僵硬膝步态（SKG）的慢性偏瘫患者在行走时，通过肌肉力矩获得的肌肉协同收缩情况。
横断面研究。
健康中心和社区医院的临床运动分析实验室。
12 名偏瘫患者（平均年龄±标准差为 49.3±12.5 岁）在患病 6 个月后出现 SKG 并行走，12 名健康成年人（平均年龄±标准差为 23.5±7.7 岁）。
偏瘫患者以其自然行走速度行走，而健康成年人以其自然和缓慢行走速度行走。对双侧下肢进行时空、动力学和运动学步态参数的测定。使用肌电驱动模型，在第一（DS1）和第二（DS2）双支撑和单支撑（SS）阶段以及摆动阶段（SW）计算膝关节和踝关节的协同收缩指数。
结果显示，慢性卒中患者在 DS1 阶段患侧踝关节协同收缩减少，膝关节协同收缩增加；DS2 阶段患侧踝关节协同收缩增加；SW 阶段患侧膝关节协同收缩增加。非患侧在 SS 阶段膝关节协同收缩较高。
SKG 偏瘫患者行走时双侧的协同收缩增加，可能是一种增加行走稳定性的适应性策略，因为它可能与痉挛有关，但也可能导致高代谢成本。
本研究获得的信息可用于支持专注于运动控制选择性的康复计划，例如力量或功率训练。
