Bai Xuefei, Ewins David, Crocombe Andrew D, Xu Wei
Department of Mechanical Engineering Sciences, University of Surrey, Guildford, United Kingdom.
Gait Laboratory, Queen Mary's Hospital, Roehampton, London, United Kingdom.
PLoS One. 2017 Jul 13;12(7):e0180836. doi: 10.1371/journal.pone.0180836. eCollection 2017.
Improved walking comfort has been linked with better bio-mimicking of the prosthetic ankle. This study investigated if a hydraulic ankle/foot can provide enough motion in both the sagittal and frontal planes during level and camber walking and if the hydraulic ankle/foot better mimics the biological ankle moment pattern compared with a fixed ankle/foot device. Five active male unilateral trans-femoral amputees performed level ground walking at normal and fast speeds and 2.5° camber walking in both directions using their own prostheses fitted with an "Echelon" hydraulic ankle/foot and an "Esprit" fixed ankle/foot. Ankle angles and the Trend Symmetry Index of the ankle moments were compared between prostheses and walking conditions. Significant differences between prostheses were found in the stance plantarflexion and dorsiflexion peaks with a greater range of motion being reached with the Echelon foot. The Echelon foot also showed significantly improved bio-mimicry of the ankle resistance moment in all walking conditions, either compared with the intact side of the same subject or with the "normal" mean curve from non-amputees. During camber walking, both types of ankle/foot devices showed similar changes in the frontal plane ankle angles. Results from a questionnaire showed the subjects were more satisfied with Echelon foot.
行走舒适度的提高与更好地仿生假肢脚踝有关。本研究调查了液压脚踝/足部在平路和外倾行走时能否在矢状面和额状面提供足够的运动，以及与固定脚踝/足部装置相比，液压脚踝/足部是否能更好地模拟生物脚踝力矩模式。五名活跃的男性单侧股骨截肢者使用配备“梯队”液压脚踝/足部和“埃斯普瑞特”固定脚踝/足部的自己的假肢，以正常和快速速度进行平路行走，并在两个方向上进行2.5°外倾行走。比较了不同假肢和行走条件下的脚踝角度和脚踝力矩的趋势对称指数。在支撑期跖屈和背屈峰值方面，不同假肢之间存在显著差异，“梯队”足部达到了更大的运动范围。与同一受试者的健侧相比，或者与非截肢者的“正常”平均曲线相比，“梯队”足部在所有行走条件下的脚踝阻力力矩仿生效果也显著改善。在外倾行走期间，两种类型的脚踝/足部装置在额状面脚踝角度上显示出相似的变化。问卷调查结果显示，受试者对“梯队”足部更满意。
