EFFECT OF USING A ROBOTIC AFO ON GAIT FUNCTION AND ELECTROENCEPHALOGRAPHY IN A SINGLE CASE WITH STROKE HEMIPLEGIA

¹Teikyo Heisei University, Department of Physiotherapy, Tokyo, Japan

Background: Rehabilitation using robots helps patients perform accurate, repetitive, and voluntary exercises. This has the advantage that motor learning is effectively performed. Walking support robots can be broadly classified into two types: double-legged type that covers both lower limbs from the pelvis and each part type that assists the movement of each joint such as the knee, foot, and waist. One of the typical robots of each part type is robotic ankle-foot orthosis (AFO) . Robotic AFO has a load sensor on the sole of the brace. Based on the sensor information, they assist the ankle plantar flexion and dorsiflexion movements during walking. In the report of kinematic effects for patients with stroke hemiplegia using robotic AFO, the walking speed and the left-right symmetry of step length and one-leg support time improved after the intervention. In the report of cerebral blood flow dynamics for people with stroke hemiplegia, it was reported that the medial primary motor cortex on the lesion side significantly improved when using robotic AFO compared to when using AFO. However, there are no reports of joint angle during gait and observation of EEG activity.

Purpose: The purpose of this study was to discuss gait analysis and electroencephalogram activity for a person with post stroke hemiplegia after exercise using a robotic AFO.

Methods: The subject is a male in his 50s and was diagnosed with cerebral hemorrhage 4 years ago. He has hemiplegia on the left side and sensory dysfunction, but no cognitive problems. Outside walking is independent without using a cane or AFO. There was decreased left ankle dorsiflexion and decreased toe clearance, and slight circumduction gait was observed.
Robotic-AFO used Cocoroe AAD manufactured by OG Wellness. The protocol consisted of the pre-intervention evaluation, the 15-minute walking exercise using R-AFO, and the post-intervention evaluation. Evaluation items were the analysis of each walking factor using Step Labo and mesuaring EEG. EEG was measured using a dry type Alltire made by Creact. The measurement area was a total of 8 channels (Fp1, Fp2, Fz, T7, T8, Pz, O1, O2).

Results: ”Maximum toe height”, ”Minimum toe height” and ”Ankle angle at IC”　in left side in gait factors of post-intervention evaluation were shown improvement. EEG results showed changes in power values (wave peak distance from baseline) in all channels in the post-intervention evaluation.

Conclusions: The result of gait analysis showed that left ankle dorsiflexion and toe clearance improved after using Robotic AFO. Robotic AFO guides the heel contact at IC and promotes the forward movement of the center of gravity from LR to MS. And then, It assists ankle dorsiflexion during the swing phase and promotes smooth lower limb movement. This walking exercise and its repetition were considered to influence the result. Furthermore, the results of this walking factor were considered to be somehow related to the changes of the motor and cognitive -related areas of the frontal lobe of EEG.
Part of this research was introduced in "Community-based care system 25(2).2023".

Implications: Robotic AFO is expected as one of new rehabilitation treatments.

Funding acknowledgements: This work was supported by JSPS KAKENHI Grant Number JP19K19802.

Keywords:
Robotic AFO
Stroke hemiplegia
Single case study

Topics:
Innovative technology: robotics
Neurology: stroke

Did this work require ethics approval? Yes

Institution: Teikyo Heisei University

Committee: The Ethics Committee of Teikyo Heisei University

Ethics number: 2022-041