Effects of a robot-assisted training of grasp and pronation/supination in chronic stroke: a pilot study

Karen SG Chua,Olivier Lambercy,Roger Gassert,Chee Leong Teo,Theodore E Milner,Christopher WK Kuah,Ludovic Dovat,Etienne Burdet,Hong Yun,Seng Kwee Wee

doi:10.1186/1743-0003-8-63

Abstract

BackgroundRehabilitation of hand function is challenging, and only few studies have investigated robot-assisted rehabilitation focusing on distal joints of the upper limb. This paper investigates the feasibility of using the HapticKnob, a table-top end-effector device, for robot-assisted rehabilitation of grasping and forearm pronation/supination, two important functions for activities of daily living involving the hand, and which are often impaired in chronic stroke patients. It evaluates the effectiveness of this device for improving hand function and the transfer of improvement to arm function.MethodsA single group of fifteen chronic stroke patients with impaired arm and hand functions (Fugl-Meyer motor assessment scale (FM) 10-45/66) participated in a 6-week 3-hours/week rehabilitation program with the HapticKnob. Outcome measures consisted primarily of the FM and Motricity Index (MI) and their respective subsections related to distal and proximal arm function, and were assessed at the beginning, end of treatment and in a 6-weeks follow-up.ResultsThirteen subjects successfully completed robot-assisted therapy, with significantly improved hand and arm motor functions, demonstrated by an average 3.00 points increase on the FM and 4.55 on the MI at the completion of the therapy (4.85 FM and 6.84 MI six weeks post-therapy). Improvements were observed both in distal and proximal components of the clinical scales at the completion of the study (2.00 FM wrist/hand, 2.55 FM shoulder/elbow, 2.23 MI hand and 4.23 MI shoulder/elbow). In addition, improvements in hand function were observed, as measured by the Motor Assessment Scale, grip force, and a decrease in arm muscle spasticity. These results were confirmed by motion data collected by the robot.ConclusionsThe results of this study show the feasibility of this robot-assisted therapy with patients presenting a large range of impairment levels. A significant homogeneous improvement in both hand and arm function was observed, which was maintained 6 weeks after end of the therapy.

Highlights

Rehabilitation of hand function is challenging, and only few studies have investigated robot-assisted rehabilitation focusing on distal joints of the upper limb
Robots designed to accurately control interaction forces and progressively adapt assistance/resistance to the patients’ abilities can record the patient’s motion and interaction forces to objectively and precisely quantify motor performance, monitor progress, and automatically adapt therapy to the patient’s state. Studies with robots such as the MIT-Manus, the ARM Guide or the MIME have demonstrated improved proximal arm function after stroke [5,6,7,8], these improvements did not transfer to the distal arm function which is necessary for most Activities of Daily Living (ADL) [9,10,11]
Inclusion criteria were subjects aged between 21 and 85 years with impaired hand opening but capable of partial hand and arm movement corresponding to proximal upper limb motor power graded 3-5 out of 5 on the Oxford Medical Research Council (MRC) scale, distal upper subject age gender (M/F)

Summary

Introduction

Rehabilitation of hand function is challenging, and only few studies have investigated robot-assisted rehabilitation focusing on distal joints of the upper limb. Robots designed to accurately control interaction forces and progressively adapt assistance/resistance to the patients’ abilities can record the patient’s motion and interaction forces to objectively and precisely quantify motor performance, monitor progress, and automatically adapt therapy to the patient’s state Studies with robots such as the MIT-Manus, the ARM Guide or the MIME have demonstrated improved proximal arm function after stroke [5,6,7,8], these improvements did not transfer to the distal arm function which is necessary for most Activities of Daily Living (ADL) [9,10,11]. Several studies indicate a generalization effect of distal arm training, e.g. hand and wrist, on proximal arm function, i.e. elbow and shoulder, which may lead to improved control of the entire arm [10,12,13]

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Discussion

Conclusion