Dutta Anirban, Kobetic Rudi, Triolo Ronald
Universitätsklinikum, Georg-August-Universität, Goettingen, Germany.
IEEE Int Conf Rehabil Robot. 2011;2011:5975383. doi: 10.1109/ICORR.2011.5975383.
Functional Electrical Stimulation (FES) facilitates walking after paralysis by activating the muscles of the lower extremities. The FES-assisted stepping triggered either by a manual switch (switch-trigger), or by an electromyogram-based gait event detector (EMG-trigger) were presented in random order to two subjects with incomplete spinal cord injuries (iSCI) during ten trials over two alternate days. Subject iSCI-1 (C6 ASIA C) was non-ambulatory without the assistance of FES and could stand but not initiate a step volitionally. Subject iSCI-2 (T1 ASIA D) could walk only short distances with great difficulty without FES. Gait kinematics and kinetics were captured during FES-assisted over-ground walking with a rolling walker under laboratory conditions. Gait parameters including speed, left and right step length, left and right double support duration, left and right swing phase durations were extracted from the kinematic data. Mean, standard deviation, coefficient of variation, and 95% confidence interval were computed for each gait parameter under each triggering condition. The ground reaction forces were recorded for both the subjects while upper body support provided by the instrumented walker was recorded for iSCI-2. One way analysis of variance (ANOVA) was performed to determine whether significant differences existed in gait parameters between command sources. The left and right double support duration were significantly lower (p<0.05) during EMG-triggered gait than switch-triggered for iSCI-1. The average normal ground reaction force was significantly (p<0.05) higher during EMG-triggered gait than switch-triggered for iSCI-1 and iSCI-2. The average body weight support on the walker was significantly lower for EMG-triggered gait than switch-triggered one for iSCI-2. The results suggest that less user effort was needed when walking with EMG-triggered stepping than with manual switch trigger.
功能性电刺激（FES）通过激活下肢肌肉来促进瘫痪后的行走。在两天内交替进行的十次试验中，以随机顺序向两名不完全性脊髓损伤（iSCI）患者呈现由手动开关触发（开关触发）或基于肌电图的步态事件检测器触发（肌电图触发）的FES辅助步幅。iSCI-1患者（C6 ASIA C级）在没有FES辅助的情况下无法行走，能够站立但无法自主起步。iSCI-2患者（T1 ASIA D级）在没有FES的情况下只能艰难地行走很短的距离。在实验室条件下，使用滚动助行器进行FES辅助的地面行走时，记录步态运动学和动力学数据。从运动学数据中提取步态参数，包括速度、左右步长、左右双支撑持续时间、左右摆动相持续时间。计算每种触发条件下每个步态参数的平均值、标准差、变异系数和95%置信区间。记录两名患者的地面反作用力，同时记录iSCI-2患者由仪器化助行器提供的上身支撑力。进行单因素方差分析（ANOVA）以确定指令源之间的步态参数是否存在显著差异。对于iSCI-1患者，肌电图触发步态期间的左右双支撑持续时间明显低于（p<0.05）开关触发步态。对于iSCI-1和iSCI-2患者，肌电图触发步态期间的平均正常地面反作用力明显高于（p<0.05）开关触发步态。对于iSCI-2患者，肌电图触发步态时助行器上的平均体重支撑明显低于开关触发步态。结果表明，与手动开关触发相比，肌电图触发步幅行走时所需的用户努力更少。
