Can a passive unilateral hip exosuit diminish walking asymmetry? A randomized trial

Kayla Kowalczyk; Mukul Mukherjee; Philippe Malcolm

doi:10.1186/s12984-023-01212-w

Can a passive unilateral hip exosuit diminish walking asymmetry? A randomized trial

J Neuroeng Rehabil. 2023 Jul 12;20(1):88. doi: 10.1186/s12984-023-01212-w.

Authors

Kayla Kowalczyk^{1

2}, Mukul Mukherjee¹, Philippe Malcolm³

Affiliations

¹ Department of Biomechanics and Center for Research in Human Movement Variability, University of Nebraska at Omaha, 6160 University Drive, Omaha, NE, 68182-0860, USA.
² UGA Concussion Research Laboratory, Department of Kinesiology, University of Georgia, Athens, GA, USA.
³ Department of Biomechanics and Center for Research in Human Movement Variability, University of Nebraska at Omaha, 6160 University Drive, Omaha, NE, 68182-0860, USA. pmalcolm@unomaha.edu.

Abstract

Background: Asymmetric walking gait impairs activities of daily living in neurological patient populations, increases their fall risk, and leads to comorbidities. Accessible, long-term rehabilitation methods are needed to help neurological patients restore symmetrical walking patterns. This study aimed to determine if a passive unilateral hip exosuit can modify an induced asymmetric walking gait pattern. We hypothesized that a passive hip exosuit would diminish initial- and post-split-belt treadmill walking after-effects in healthy young adults.

Methods: We divided 15 healthy young adults evenly between three experimental groups that each completed a baseline trial, an adaptation period with different interventions for each group, and a post-adaptation trial. To isolate the contribution of the exosuit we compared a group adapting to the exosuit and split-belt treadmill (Exo-Sb) to groups adapting to exosuit-only (Exo-only) and split-belt only (Sb-only) conditions. The independent variables step length, stance time, and swing time symmetry were analyzed across five timepoints (baseline, early- and late adaptation, and early- and late post-adaptation) using a 3 × 5 mixed ANOVA.

Results: We found significant interaction and time effects on step length, stance time and swing time symmetry. Sb-only produced increased step length asymmetry at early adaptation compared to baseline (p < 0.0001) and an after-effect with increased asymmetry at early post-adaptation compared to baseline (p < 0.0001). Exo-only increased step length asymmetry (in the opposite direction as Sb-only) at early adaptation compared to baseline (p = 0.0392) but did not influence the participants sufficiently to result in a post-effect. Exo-Sb produced similar changes in step length asymmetry in the same direction as Sb-only (p = 0.0014). However, in contrast to Sb-only there was no significant after-effect between early post-adaptation and baseline (p = 0.0885).

Conclusion: The passive exosuit successfully diminished asymmetrical step length after-effects induced by the split-belt treadmill in Exo-Sb. These results support the passive exosuit's ability to alter walking gait patterns.

Keywords: Adaptation; Biomechanics; Exoskeleton; Split-belt; Walking.

Publication types

Randomized Controlled Trial
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Activities of Daily Living*
Gait
Humans
Walking*
Young Adult

Grants and funding

P20 GM109090/GM/NIGMS NIH HHS/United States