Effects of a Robotic Lower-Limb Orthosis on Gait Based on the Analysis of sEMG Signals and Kinematic Data: Preliminary Results

Devices such as robotic orthosis and exoskeletons oriented to assist mobility are required to support rehabilitation treatments and to improve quality of life of disability population. In order to evaluate these devices, kinematic data and myoelectric activity are used, thus, robust protocols and analysis can demonstrate the impact of this technology. The aim of this work is to study the effects on surface electromyography (sEMG) and inertial signals for healthy subjects and chronic stroke survivors when using a robotic lower-limb orthosis (ALLOR). Kinematics effects evaluated on hip flexion-extension angles show that they present high bilateral reproducibility for both groups of four healthy subjects and one post-stroke patient, achieving a strong concordance correlation (c > 0.80). Furthermore, a strong concordance correlation (c > 0.80) of knee. Flexion/extension angles was achieved at one side for five healthy subjects and one post-stroke patient. On the other hand, effects evaluated on myoelectric activity through sEMG show that, for a post-stroke patient, a significant increase (p < 0.05) was obtained for activation over the Erector Spinae muscle at L4 level and Semitendinosus muscle at the left side. For the other post-stroke patient, a significant decrease (p < 0.05) was noticed for activation over the Erector Spinae muscle at L4 level and Rectus femoris muscle. This research also presents results related to the satisfaction level regarding the use of ALLOR through the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0). From the outcomes of this research, we believe our results may be used to improve protocols for post-stroke rehabilitation.