Evaluation of a passive pediatric leg exoskeleton during gait.
Ontology highlight
ABSTRACT: Background
Children with hemiparesis are commonly prescribed ankle foot orthoses to help improve gait; however, these orthoses often result in only small and variable changes in gait. Research with adult stroke survivors has suggested that orthoses that extend beyond the ankle using long, passive tendon-like structures (i.e. exotendons) can improve walking.Objectives
The aim of this study was to quantify the impact of an exotendon-based exoskeleton on pediatric gait.Study design
Repeated-measures study.Methods
Two typically-developing children and two children with hemiparesis completed a gait analysis, walking without and with the exoskeleton. The exotendon was tested at three stiffness levels.Results
All children were able to walk comfortably with the exoskeleton, with minimal changes in step width. Walking speed increased and lower limb joint symmetry improved for the children with hemiparesis with the exoskeleton. Each participant had changes in muscle activity while walking with the exoskeleton, although the impact on specific muscles and response to exotendon stiffness varied.Conclusion
Exotendon-based exoskeletons may provide an alternative solution for optimizing gait in therapy and in the community for children with hemiparesis. Determining the optimal stiffness and configuration for each child is an important area of future research.
SUBMITTER: Zistatsis J
PROVIDER: S-EPMC8916307 | biostudies-literature | 2021 Apr
REPOSITORIES: biostudies-literature
Publications
Evaluation of a passive pediatric leg exoskeleton during gait.
Zistatsis Jessica J Peters Keshia M KM Ballesteros Daniel D Feldner Heather A HA Feldner Heather A HA Bjornson Kristie K Steele Katherine M KM
Prosthetics and orthotics international 20210401 2
<h4>Background</h4>Children with hemiparesis are commonly prescribed ankle foot orthoses to help improve gait; however, these orthoses often result in only small and variable changes in gait. Research with adult stroke survivors has suggested that orthoses that extend beyond the ankle using long, passive tendon-like structures (i.e. exotendons) can improve walking.<h4>Objectives</h4>The aim of this study was to quantify the impact of an exotendon-based exoskeleton on pediatric gait.<h4>Study des ...[more]
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Project description:BackgroundPost-stroke hemiparesis is usually considered a unilateral motor control deficit of the paretic leg, while the non-paretic leg is assumed to compensate for paretic leg impairments and have minimal to no deficits. While the non-paretic leg electromyography (EMG) patterns are clearly altered, how the non-paretic leg acts to compensate remains to be established.MethodsKinesiological data were recorded from sixty individuals with chronic hemiparesis (age: 60.9, SD=12.6 years, 21 females, 28 right hemiparetic, time since stroke: 4.5 years, SD 3.9 years), divided into three speed-based groups, and twenty similarly aged healthy individuals (age: 65.1, SD=10.4 years, 15 females). All walked on an instrumented split-belt treadmill at their self-selected speed and control subjects also walked at slower speeds matching those of the persons with hemiparesis. We determined the differences in magnitude and timing of non-paretic EMG activity relative to healthy control subjects in four pre-defined regions of stance phase of the gait cycle.FindingsIntegrated EMG activity and EMG timing in the non-paretic leg were different in many muscles. Multiple compensatory patterns identified included: increased EMG output when the muscle was typically active in controls and novel compensatory EMG patterns that appeared to provide greater propulsion or support with little evidence of impaired motor performance.InterpretationMost novel compensations were made possible by altered kinematics of the paretic and non-paretic leg (i.e., early stance plantarflexor activity provided propulsion due to the decreased advancement of the non-paretic foot) while others (late single limb stance knee extensor and late stance hamstring activity) appeared to be available mechanisms for increasing propulsion.
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