Amsterdam UMC, University of Amsterdam, Rehabilitation Medicine, Amsterdam Movement Sciences, Meibergdreef 9, Amsterdam, The Netherlands.
Amsterdam UMC, University of Amsterdam, Rehabilitation Medicine, Amsterdam Movement Sciences, Meibergdreef 9, Amsterdam, The Netherlands.
Gait Posture. 2022 Feb;92:71-76. doi: 10.1016/j.gaitpost.2021.11.023. Epub 2021 Nov 20.
In individuals with unilateral plantar flexor weakness, the second peak of the vertical ground reaction force (GRF) is decreased. This leads to a higher ground reaction force, e.g. impact, of the contralateral leg, potentially explaining quadriceps muscle and/or knee joint pain. Energy cost optimized dorsal leaf ankle-foot-orthoses (AFOs) may increase the push-off ground reaction force, which in turn could lead to lower impact forces on the contralateral leg.
Nine subjects with unilateral plantar flexor weakness were provided a dorsal leaf AFO with a stiffness primarily optimized for energy cost. Using 3D gait analyses peak vertical GRF during loading response with and without AFO, and the symmetry between the legs in peak GRF were calculated. Peak GRF and symmetry were compared with reference data of 23 healthy subjects.
The contralateral leg showed a significant higher peak vertical GRF (12.0 ± 0.9 vs 11.2 ± 0.6 N/kg, p = 0.005) compared to healthy reference data. When walking with AFO, the peak vertical GRF of the contralateral leg significantly reduced (from 12.0 ± 0.9 to 11.4 ± 0.7 N/kg, p = 0.017) and symmetry improved compared to no AFO (from 0.93 ± 0.06 to 1.01 ± 0.05, p < 0.001).
In subjects with unilateral plantar flexor weakness, impact force on the contralateral leg was increased when compared to healthy subjects and dorsal leaf AFOs optimized for energy cost substantially reduced this force and improved impact symmetry when compared to walking without AFO. This indicates that dorsal leaf AFOs may reduce pain resulting from increased impact forces during gait in the contralateral leg in people with unilateral plantar flexor weakness.
在单侧跖屈肌无力的个体中，垂直地面反作用力（GRF）的第二峰值降低。这导致对侧腿部的地面反作用力更高，例如冲击力，可能导致股四头肌肌肉和/或膝关节疼痛。能量优化的背叶踝足矫形器（AFO）可能会增加蹬离地面的反作用力，这反过来又可能导致对侧腿部的冲击力降低。
1）与健康受试者相比，单侧跖屈肌无力者的对侧腿部冲击力是否增加？2）与不使用 AFO 行走相比，能量优化的 AFO 是否会降低单侧跖屈肌无力者的冲击力并改善腿部冲击力的对称性？
为 9 名单侧跖屈肌无力者提供了一个主要针对能量成本进行优化的背叶 AFO。使用 3D 步态分析，在有和没有 AFO 的情况下计算加载响应期间的垂直 GRF 峰值，以及腿部之间 GRF 峰值的对称性。将 GRF 峰值和对称性与 23 名健康受试者的参考数据进行比较。
与健康参考数据相比，对侧腿部的垂直 GRF 峰值明显更高（12.0±0.9 与 11.2±0.6 N/kg，p=0.005）。当使用 AFO 行走时，对侧腿部的垂直 GRF 峰值显著降低（从 12.0±0.9 降低至 11.4±0.7 N/kg，p=0.017），与不使用 AFO 相比，对称性也得到改善（从 0.93±0.06 增加至 1.01±0.05，p<0.001）。
与健康受试者相比，单侧跖屈肌无力者的对侧腿部冲击力增加，而针对能量成本进行优化的背叶 AFO 可显著降低该力，并改善与不使用 AFO 行走相比的冲击力对称性。这表明，在单侧跖屈肌无力者中，背叶 AFO 可能会减轻步态中对侧腿部因冲击力增加而导致的疼痛。
