One of the recommended post-stroke gait rehabilitation treatments is the use of an ankle–foot orthosis. In clinical practice, it is important to adjust the torque of the ankle–foot orthosis assistance to suit each patient’s body function and gait ability. The present study aimed to investigate the effect of changing the plantar flexion resistance of the ankle–foot orthosis on the post-stroke gait kinematics and kinetics during the early stance phase using a musculoskeletal model and an ankle–foot orthosis model. The subject was a male with post-stroke left hemiplegia who could walk independently without an ankle–foot orthosis and/or cane. The subject walked at a self-selected speed under the no ankle–foot orthosis condition and three ankle–foot orthosis conditions, each with a different plantar flexion resistive torque. A motion analysis system was used to measure the following spatiotemporal parameters: gait speed, step length, cadence, and step length ratio. In addition, the ankle angle of the paretic side, ankle torque of the paretic side, and plantar flexion resistance torque of the ankle–foot orthosis were calculated using a musculoskeletal model and an ankle–foot orthosis model. The results showed that the gait speed and step length ratio of all ankle–foot orthosis conditions were improved compared with the no ankle–foot orthosis condition. In particular, the condition with the smallest torque was the most symmetric of the four walking conditions. The condition with the smallest torque also resulted in the greatest increase in the dorsiflexion angle of the paretic side at heel contact. The internal dorsiflexion torque was most increased in the ankle–foot orthosis condition with the smallest torque for this subject. The simulation of the post-stroke gait in the present study contributes to the development of more effective gait rehabilitation treatment methods using an ankle–foot orthosis.

中文翻译：

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踝足矫形器对步态运动学和动力学的影响：使用肌肉骨骼模型和矫形器模型的中风后步态的案例研究

建议的中风后步态康复治疗方法之一是使用踝足矫形器。在临床实践中，重要的是调整踝足矫形器辅助装置的扭矩以适合每个患者的身体功能和步态。本研究的目的是使用肌肉骨骼模型和踝足矫形器模型研究在站立初期，改变踝足矫形器的足底屈曲阻力对中风后步态运动学和动力学的影响。受试者为一名中风后左偏瘫的男性，可以独立行走而没有踝足矫形器和/或手杖。在无踝足矫形器情况和三种踝足矫形器情况下，受试者以自行选择的速度行走，每种情况下足底屈曲阻力均不同。运动分析系统用于测量以下时空参数：步态速度，步长，步频和步长比。此外，还使用肌肉骨骼模型和踝足矫形器模型计算了etic侧的踝角，the侧的踝部扭矩以及踝足矫形器的足底屈曲阻力扭矩。结果表明，与无踝足矫形器相比，所有踝足矫形器的步态速度和步长比均得到改善。特别地，具有最小扭矩的状况是四个行走状况中最对称的。扭矩最小的情况也导致跟部接触时坐骨侧面的背屈角最大增加。在踝足矫形器的情况下，该患者的背背屈内扭矩最大，而该受试者的扭矩最小。在本研究中，对中风后步态的模拟有助于开发使用脚踝矫形器的更有效的步态康复治疗方法。