Berenpas Frank, Schiemanck Sven, Beelen Anita, Nollet Frans, Weerdesteyn Vivian, Geurts Alexander
Department of Rehabilitation, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands.
Department of Rehabilitation Medicine, Leiden University Medical Center, Leiden, the Netherlands.
Restor Neurol Neurosci. 2018;36(4):547-558. doi: 10.3233/RNN-180822.
Contralesional 'drop foot' after stroke is usually treated with an ankle-foot orthosis (AFO). However, AFOs may hamper ankle motion during stance. Peroneal functional electrical stimulation (FES) is an alternative treatment that provides active dorsiflexion and allows normal ankle motion. Despite this theoretical advantage of FES, the kinematic and kinetic differences between AFO and FES have been scarcely investigated.
To test whether walking with implanted FES leads to improvements in stance stability, propulsion, and swing initiation compared to AFO.
A 4-channel peroneal nerve stimulator (ActiGait ®) was implanted in 22 chronic patients after stroke. Instrumented gait analyses were performed during comfortable walking up to 26 weeks (n = 10) or 52 weeks (n = 12) after FES-system activation. Kinematics of knee and ankle (stance and swing phase) and kinetics (stance phase) of gait were determined, besides spatiotemporal parameters. Finally, we determined whether differences between devices regarding late stance kine(ma)tics correlated with those regarding the swing phase.
In mid-stance, knee stability improved as the peak knee extension velocity was lower with FES (β = 18.1°/s, p = 0.007), while peak ankle plantarflexion velocity (β = -29.2°/s, p = 0.006) and peak ankle plantarflexion power (β = -0.2 W/kg, p = 0.018) were higher with FES compared to AFO. With FES, the ground reaction force (GRF) vector at peak ankle power (i.e., 'propulsion') was oriented more anteriorly (β = -1.1°, p = 0.001). Similarly, the horizontal GRF (β = -0.8% body mass, p = 0.003) and gait speed (β = 0.03 m/s, p = 0.015) were higher. An increase in peak ankle plantarflexion velocity and a more forward oriented GRF angle during late stance were moderately associated with an increase in hip flexion velocity during initial swing (rs = 0.502, p = 0.029 and rs = 0.504, p = 0.028, respectively).
This study substantiates the evidence that implantable peroneal FES as a treatment for post-stroke drop foot may be superior over AFO in terms of knee stability, ankle plantarflexion power, and propulsion.
中风后对侧“垂足”通常采用踝足矫形器（AFO）进行治疗。然而，AFO可能会在站立期妨碍踝关节活动。腓总神经功能性电刺激（FES）是一种替代治疗方法，可提供主动背屈并允许踝关节正常活动。尽管FES具有这一理论优势，但AFO和FES之间的运动学和动力学差异鲜有研究。
测试与AFO相比，植入式FES辅助行走是否能改善站立稳定性、推进力和摆动起始。
在22例中风后慢性患者体内植入四通道腓总神经刺激器（ActiGait®）。在FES系统激活后长达26周（n = 10）或52周（n = 12）的舒适步行过程中进行仪器化步态分析。除时空参数外，还测定了膝关节和踝关节的运动学（站立期和摆动期）以及步态的动力学（站立期）。最后，我们确定了两种装置在站立后期运动学方面的差异是否与摆动期的差异相关。
在站立中期，FES组膝关节伸展峰值速度较低，膝关节稳定性得到改善（β = 18.1°/s，p = 0.007），而与AFO相比，FES组踝关节跖屈峰值速度（β = -29.2°/s，p = 0.006）和踝关节跖屈峰值功率（β = -0.2 W/kg，p = 0.018）更高。使用FES时，踝关节功率峰值（即“推进力”）时的地面反作用力（GRF）向量更向前（β = -1.1°，p = 0.001）。同样，水平GRF（β = -0.8%体重，p = 0.003）和步态速度（β = 0.03 m/s，p = 0.015）也更高。站立后期踝关节跖屈峰值速度增加和GRF角度更向前与初始摆动期髋关节屈曲速度增加中度相关（rs分别为0.502，p = 0.029和rs为0.504，p = 0.028）。
本研究证实了以下证据：作为中风后垂足的一种治疗方法，植入式腓总神经FES在膝关节稳定性、踝关节跖屈功率和推进力方面可能优于AFO。
