Brief report
Reducing Robotic Guidance During Robot-Assisted Gait Training Improves Gait Function: A Case Report on a Stroke Survivor

https://doi.org/10.1016/j.apmr.2012.11.016Get rights and content

Abstract

Objective

To test the feasibility of patient-cooperative robotic gait training for improving locomotor function of a chronic stroke survivor with severe lower-extremity motor impairments.

Design

Single-subject crossover design.

Setting

Performed in a controlled laboratory setting.

Participant

A 62-year-old man with right temporal lobe ischemic stroke was recruited for this study. The baseline lower-extremity Fugl-Meyer score of the subject was 10 on a scale of 34, which represented severe impairment in the paretic leg. However, the subject had a good ambulation level (community walker with the aid of a stick cane and ankle-foot orthosis) and showed no signs of sensory or cognitive impairments.

Interventions

The subject underwent 12 sessions (3 times per week for 4wk) of conventional robotic training with the Lokomat, where the robot provided full assistance to leg movements while walking, followed by 12 sessions (3 times per week for 4wk) of patient-cooperative robotic control training, where the robot provided minimal guidance to leg movements during walking.

Main Outcome Measures

Clinical outcomes were evaluated before the start of the intervention, immediately after 4 weeks of conventional robotic training, and immediately after 4 weeks of cooperative control robotic training. These included: (1) self-selected and fast walking speed, (2) 6-minute walk test, (3) Timed Up & Go test, and (4) lower-extremity Fugl-Meyer score.

Results

Results showed that clinical outcomes changed minimally after full guidance robotic training, but improved considerably after 4 weeks of reduced guidance robotic training.

Conclusions

The findings from this case study suggest that cooperative control robotic training is superior to conventional robotic training and is a feasible option to restoring locomotor function in ambulatory stroke survivors with severe motor impairments. A larger trial is needed to verify the efficacy of this advanced robotic control strategy in facilitating gait recovery after stroke.

Section snippets

Participant

For the purpose of this study, we recruited a 62-year-old man with right temporal lobe ischemic stroke resulting in left-sided hemiparesis. He was enrolled in the study 10 months after the onset of stroke. The details of baseline subject characteristics are provided in table 1. At the time of recruitment, the subject had severe motor impairments as characterized by a lower-extremity Fugl-Meyer motor score of 10 on a scale of 34.12 However, his ambulatory function was preserved, and he was

Results

The average speed at which the subject trained was quite similar between the 2 modes of training (full guidance training: .75±.06m/s, reduced guidance training: .82±.09m/s). This was also the case for the average distance walked by the subject during the 2 modes of training (full guidance training: 2935±413m, reduced guidance training: 3181±392m). Yet, changes in the clinical outcomes after the 2 modes of training differed substantially (fig 1B). There were minimal improvements in the clinical

Discussion

The purpose of this case study was 2-fold: (1) to test the feasibility of patient-cooperative robotic training as a gait rehabilitation option for stroke survivors with severe motor impairments, and (2) to pilot test whether robotic control strategies that encourage active movements is superior to control strategies that completely assist movements in facilitating gait recovery after stroke. Four weeks of conventional robotic control training on a chronic stroke survivor with marked paresis did

Conclusions

Robot-assisted gait therapy is a promising intervention, because it enables the delivery of locomotion therapy at a high dosage in a safe environment. However, it may be important to incorporate appropriate control algorithms, and therefore the patient is actively engaged in the learning process and in the physical training as well. This case study establishes the proof of concept for using reduced guidance robotic training as opposed to full guidance robotic training. Moreover, the results

Supplier

  • a.

    Hocoma AG, Industriestrasse 4, CH-8604 Volketswil Switzerland.

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Supported by Machines Assisting Recovery From Stroke - Rehabilitation Engineering Research Center (grant no. H133E0700130) funded by the National Institute on Disability and Rehabilitation Research.

No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organization with which the authors are associated.

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Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.