Department of Clinical Neurophysiology, University Medical Center Göttingen, 37075 Göttingen, Germany.
Restor Neurol Neurosci. 2013;31(5):557-69. doi: 10.3233/RNN-120283.
Functional electrical stimulation represents an alternative to conventional and passive ankle foot orthosis (AFO) for the treatment of stroke-related drop foot. We evaluated the implantable 4-channel stimulator ActiGait, which selectively and directly stimulates the peroneal nerve. In addition, it bypasses the need for surface electrodes and cables.
Walking speed (10-meter gait test, [m/s]) and walking endurance (6-minute gait test [m/6min]) of 5 patients were tested prior to, as well as 6 and 12 weeks after, the implantation of the ActiGait implantable drop foot stimulator system. In addition, ankle joint angles were assessed during specific phases of the gait cycle, i.e. initiation angle (IA) at the first contact of the foot to the floor, initial plantar flexion (IPF), dorsiflexion (DF) and final plantar flexion (FPF) in [°] during stance phase. The ankle joint angles were measured at baseline and 12 weeks after ActiGait implantation.
At the first follow-up, patients' gait speed was found to have increased (0.55; 0.77 m/s) as had walking endurance (211; 260 m). Improvement in gait speed (0.55; 0.77 m/s) and endurance (214; 248 m) was still present after 12 weeks. In addition, gait analysis after 12 weeks revealed a nearly normal physiological initiation angle (113° vs 122°) and an increase in the initial plantar flexion (7° vs. 0°). The initiation angle (IA) represents a well-suited parameter for adequate pre-positioning of the foot at the beginning of the stance phase and is necessary to prevent stumbling and falling. Furthermore, IA is identical to the maximum achieved dorsiflexion during the swing phase of gait. Thus, analysis of the IA of subjects walking with the implantable drop foot stimulator systems ActiGait is particularly useful in showing that the implantable system restores the IA towards physiological ankle movements.
The ActiGait system increased gait speed, walking endurance and the physiology of important ankle joint kinematics. This is most likely a result of ankle dorsiflexion by active peroneal stimulation during the swing phase of gait and optimized prepositioning (IA) of the foot at the beginning of stance phase. The ActiGait system represents a therapeutic option for the treatment of patients suffering drop foot due to a cerebrovascular insult.
功能性电刺激是治疗与中风相关的足下垂的一种替代传统和被动踝足矫形器（AFO）的方法。我们评估了可植入的 4 通道刺激器 ActiGait，它可以选择性地直接刺激腓总神经。此外，它还可以绕过使用表面电极和电缆的需要。
在植入 ActiGait 可植入式足下垂刺激系统之前、植入后 6 周和 12 周，对 5 名患者的步行速度（10 米步态测试，[m/s]）和步行耐力（6 分钟步态测试 [m/6min]）进行了测试。此外，还评估了踝关节角度在步态周期的特定阶段，即在脚第一次接触地面时的起始角度（IA）、初始跖屈（IPF）、背屈（DF）和站立阶段的最终跖屈（FPF）[°]。在植入 ActiGait 后 12 周测量了踝关节角度。
在第一次随访时，发现患者的步行速度增加（0.55；0.77 m/s），步行耐力增加（211；260 m）。植入 ActiGait 后 12 周时，步行速度（0.55；0.77 m/s）和耐力（214；248 m）仍有改善。此外，12 周后的步态分析显示，起始角度（IA）接近正常的生理角度（113° vs 122°），初始跖屈增加（7° vs. 0°）。起始角度（IA）是一个很好的参数，用于在站立阶段开始时适当定位脚，并防止绊倒和跌倒。此外，IA 与步态摆动阶段中达到的最大背屈角度相同。因此，分析使用植入式足下垂刺激系统 ActiGait 行走的受试者的 IA 特别有用，可以证明植入式系统将 IA 恢复到生理踝关节运动。
ActiGait 系统提高了步行速度、步行耐力和重要踝关节运动学的生理学。这很可能是由于在步态的摆动阶段主动刺激腓总神经引起的踝关节背屈以及在站立阶段开始时对脚进行优化的预定位（IA）的结果。ActiGait 系统为治疗因脑血管损伤而患有足下垂的患者提供了一种治疗选择。
