Design and Preliminary Evaluation of a Tongue-Operated Exoskeleton System for Upper Limb Rehabilitation.

Zhenxuan Zhang,Maysam Ghovanloo,Andrew J Butler,Boris I Prilutsky,Minoru Shinohara

doi:10.3390/ijerph18168708

Abstract

Stroke is a devastating condition that may cause upper limb paralysis. Robotic rehabilitation with self-initiated and assisted movements is a promising technology that could help restore upper limb function. Previous studies have established that the tongue motion can be used to communicate human intent and control a rehabilitation robot/assistive device. The goal of this study was to evaluate a tongue-operated exoskeleton system (TDS-KA), which we have developed for upper limb rehabilitation. We adopted a tongue-operated assistive technology, called the tongue drive system (TDS), and interfaced it with the exoskeleton KINARM. We also developed arm reaching and tracking tasks, controlled by different tongue operation modes, for training and evaluation of arm motor function. Arm reaching and tracking tasks were tested in 10 healthy participants (seven males and three females, 23–60 years) and two female stroke survivors with upper extremity impairment (32 and 58 years). All healthy and two stroke participants successfully performed the tasks. One stroke subject demonstrated a clinically significant improvement in Fugl-Meyer upper extremity score after practicing the tasks in six 3-h sessions. We conclude that the TDS-KA system can accurately translate tongue commands to exoskeleton arm movements, quantify the function of the arm, and perform rehabilitation training.

Highlights

Stroke is the leading cause of adult disability in the United States
The passive (P), discrete tongue (DT), and discrete tongue hybrid (DTH) modes had no or little backward-forward displacement component, reflecting the fact that hand trajectories in these modes were generated by the robotic system exclusively in response to commands by the robot or the user to move the hand between the left and right targets
Sharp changes in hand trajectories occurred in the active region of hybrid modes Discrete tongue hybrid (DTH) and proportional tongue hybrid (PTH), indicating the switch from the tongue control to active arm control

Summary

Introduction

Stroke is the leading cause of adult disability in the United States. Of all the stroke survivors, around 80% experience different degrees of upper limb paresis, which reduces their quality of life severely [1,2]. Rehabilitation can help stroke survivors reduce disability and regain their independence [2,3]. Robot-assisted rehabilitation has been tested for its ability to improve recovery and lower the cost of stroke rehabilitation [6,7,8]. It is still not clear if robotic rehabilitation can deliver consistently better clinical outcomes compared to traditional therapy [7,8,9,10], robotic rehabilitation enables clinicians to deliver more consistent therapy with measurable results in real-time [11,12]

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Discussion

Conclusion