Motion Analysis Center & Clinical Research Center, Brooks Rehabilitation, Jacksonville, FL, USA.
Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, USA.
Clin Biomech (Bristol). 2024 Jun;116:106268. doi: 10.1016/j.clinbiomech.2024.106268. Epub 2024 May 18.
Community ambulation involves complex walking adaptability tasks such as stepping over obstacles or taking long steps, which require adequate propulsion generation by the trailing leg. Individuals post-stroke often have an increased reliance on their trailing nonparetic leg and favor leading with their paretic leg, which can limit mobility. Ankle-foot-orthoses are prescribed to address common deficits post-stroke such as foot drop and ankle instability. However, it is not clear if walking with an ankle-foot-orthosis improves inter-limb propulsion symmetry during adaptability tasks. This study sought to examine this hypothesis.
Individuals post-stroke (n = 9) that were previously prescribed a custom fabricated plantarflexion-stop articulated ankle-foot-orthosis participated. Participants performed steady-state walking and adaptability tasks overground with and without their orthosis. The adaptability tasks included obstacle crossing and long-step tasks, leading with both their paretic and nonparetic leg. Inter-limb propulsion symmetry was calculated using trailing limb ground-reaction-forces.
During the obstacle crossing task, ankle-foot-orthosis use resulted in a significant improvement in inter-limb propulsion symmetry. The orthosis also improved ankle dorsiflexion during stance, reduced knee hyperextension, increased gastrocnemius muscle activity, and increased peak paretic leg ankle plantarflexor moment. In contrast, there were no differences in propulsion symmetry during steady-state walking and taking a long-step when using the orthosis.
Plantarflexion-stop articulated ankle-foot-orthoses can improve propulsion symmetry during obstacle crossing tasks in individuals post-stroke, promoting paretic leg use and reduced reliance on the nonparetic leg.
社区步行活动涉及复杂的步行适应性任务，如跨越障碍物或迈大步，这需要后腿充分产生推进力。脑卒中后患者通常过度依赖非瘫痪侧下肢，喜欢用瘫痪侧下肢作为主导腿，这会限制其移动能力。踝足矫形器用于解决脑卒中后常见的问题，如足下垂和踝关节不稳定。然而，目前尚不清楚在进行适应性任务时，使用踝足矫形器是否能改善肢体间的推进力对称性。本研究旨在检验这一假设。
本研究纳入了 9 名曾被处方定制式跖屈限位踝足矫形器的脑卒中后患者。参与者在佩戴和不佩戴矫形器的情况下，分别在地面上进行稳态步行和适应性任务。适应性任务包括跨越障碍物和迈大步任务，分别用瘫痪侧和非瘫痪侧下肢作为主导腿。肢体间推进力对称性通过后腿地面反作用力来计算。
在跨越障碍物任务中，使用踝足矫形器可显著改善肢体间推进力对称性。矫形器还改善了站立期的踝关节背屈，减少了膝关节过伸，增加了比目鱼肌的活动，并增加了瘫痪侧踝关节跖屈肌的峰值力矩。相比之下，在佩戴矫形器进行稳态步行和迈大步时，推进力对称性没有差异。
跖屈限位踝足矫形器可改善脑卒中后患者跨越障碍物任务中的推进力对称性，促进瘫痪侧下肢的使用，减少对非瘫痪侧下肢的依赖。
