An ankle-foot orthosis (AFO) with a plantarflexion resistance function, improves post-stroke gait. An AFO with a plantarflexion resistance function not only affects the first rocker function and the weight acceptance but also the late stance phase. Achilles tendon extension is important for ankle joint function and for forward propulsion during the late stance phase; however, the effect of an AFO with a plantarflexion resistance function on the Achilles tendon is unclear. The purpose of this study was to investigate the effect of plantarflexion resistance on the extension of the Achilles tendon and the forward-propulsive force. Herein, 10 healthy adult males participated who walked under three different conditions: a no-AFO condition and two AFO conditions that had different levels of plantarflexion resistance (P1 and P2). The stiffness value of the P1 and P2 conditions was 0.56 and 1.47 Nm/°, respectively. A three-dimensional (3D) motion analysis system and a musculoskeletal model were used to assess the tendon-length change, the ground reaction force, kinematics, and kinetics data. The change in Achilles tendon length was significantly lower in the P1 and P2 conditions than the no-AFO condition. Furthermore, changes in the length of the Achilles tendon significantly decreased in the P2 condition when compared with that in the P1 condition. The peak anterior ground reaction force was significantly lower in the P2 condition than the no-AFO condition. These results suggest that excessive assist provided by an AFO prevents efficient gait by decreasing both the forward-propulsive force and tendon function.

中文翻译：

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踝足矫形器Plant屈刚度的变化对步态中跟腱和推进力的影响

具有抗plant屈功能的踝足矫形器（AFO）可改善中风后的步态。具有足底屈曲功能的AFO不仅会影响前摇杆功能和承重，还会影响后期站立阶段。跟腱延伸对脚踝关节功能和晚期站立阶段的向前推进很重要。然而，尚不清楚具有足底屈曲功能的AFO对跟腱的作用。这项研究的目的是调查足底屈曲阻力对跟腱的延伸和向前推进力的影响。本文中，有10名健康的成年男性参加，他们在三种不同的条件下行走：无AFO条件和两种具有不同程度的plant屈抵抗性（P1和P2）的AFO条件。P1和P2条件的刚度值分别为0.56和1.47 Nm /°。使用三维（3D）运动分析系统和肌肉骨骼模型来评估肌腱长度变化，地面反作用力，运动学和动力学数据。在P1和P2条件下，跟腱长度的变化明显低于无AFO条件。此外，与P1状态相比，P2状态的跟腱长度的变化显着减少。在P2状态下，峰值前地面反作用力明显低于在无AFO状态下。这些结果表明，AFO提供的过度协助会同时降低前向推进力和肌腱功能，从而阻止步态有效。使用三维（3D）运动分析系统和肌肉骨骼模型来评估肌腱长度变化，地面反作用力，运动学和动力学数据。在P1和P2条件下，跟腱长度的变化明显低于无AFO条件。此外，与P1状态相比，P2状态的跟腱长度的变化显着减少。在P2状态下，峰值前地面反作用力明显低于在无AFO状态下。这些结果表明，AFO提供的过度协助会同时降低前向推进力和肌腱功能，从而阻止步态有效。使用三维（3D）运动分析系统和肌肉骨骼模型来评估肌腱长度变化，地面反作用力，运动学和动力学数据。在P1和P2条件下，跟腱长度的变化明显低于无AFO条件。此外，与P1状态相比，P2状态的跟腱长度的变化显着减少。在P2状态下，峰值前地面反作用力明显低于在无AFO状态下。这些结果表明，AFO提供的过度协助会同时降低前向推进力和肌腱功能，从而阻止步态有效。运动学和动力学数据。在P1和P2条件下，跟腱长度的变化明显低于无AFO条件。此外，与P1状态相比，P2状态的跟腱长度的变化显着减少。在P2状态下，峰值前地面反作用力明显低于在无AFO状态下。这些结果表明，AFO提供的过度协助会同时降低前向推进力和肌腱功能，从而阻止步态有效。运动学和动力学数据。在P1和P2条件下，跟腱长度的变化明显低于无AFO条件。此外，与P1状态相比，P2状态的跟腱长度的变化显着减少。在P2状态下，峰值前地面反作用力明显低于在无AFO状态下。这些结果表明，AFO提供的过度协助会同时降低前向推进力和肌腱功能，从而阻止步态有效。在P2状态下，峰值前地面反作用力明显低于在无AFO状态下。这些结果表明，AFO提供的过度协助会同时降低前向推进力和肌腱功能，从而阻止步态有效。在P2状态下，峰值前地面反作用力明显低于在无AFO状态下。这些结果表明，AFO提供的过度协助会同时降低前向推进力和肌腱功能，从而阻止步态有效。