Citation

Aminiaghdam S, Griessbach E, Vielemeyer J, Müller R. Gait Posture 2019; 71: 38-43.

Affiliation

Department of Motion Science, Institute of Sport Science, Friedrich-Schiller-University Jena, Jena, Thuringia, Germany; Department of Neurology/Department of Orthopedic Surgery, Bayreuth Hospital, Bayreuth, Bavaria, Germany.

Copyright

(Copyright © 2019, Elsevier Publishing)

DOI

10.1016/j.gaitpost.2019.04.014

PMID

31005853

Abstract

BACKGROUND: The unexpectedness of ground-contact onset in stepping down due, e.g., to a camouflaged curb during ongoing gait may impose potential postural control challenges, which might be deteriorated when walking faster. RESEARCH QUESTION: Does traversing camouflaged versus visible curbs, at a fast walking velocity, induce more unstable body configurations, assessed by a smaller anteroposterior "margin of stability" (MoS)? METHODS: For twelve healthy participants, we investigated MoS at foot touchdown in descent and in the first recovery step from 0- and 10-cm visible and camouflaged curbs at comfortable (1.22 ± 0.08 m/s) and fast (1.71 ± 0.11 m/s) walking velocities. Three-way (velocity, elevation, visibility) and two-way (velocity, visibility) repeated-measurement ANOVAs were performed to determine their interactions on MoS, and its determining parameters, during curb negotiation and recovery step, respectively.

RESULTS: No greater postural instability when traversing a camouflaged versus visible curb at a faster walking velocity during curb descent, indicated by no three-way interaction effects on MoS. However, an elevation-by-visibility interaction showed a dramatic decrease of MoS when descending a 10-cm camouflaged versus visible curb. This was because of a farther anterior displacement of center-of-mass with a larger velocity. Furthermore, the walking velocity was independently associated with a smaller MoS and a more anteriorly-shifted center-of-mass with a higher velocity. In the recovery step, participants demonstrated a reduced stability of the body configuration when walking faster or recovering from a camouflaged than from a visible curb. The mentioned result implies that the potential to increase the base-of-support to compensate for an increased center-of-mass velocity, induced by an increased walking velocity, is limited. SIGNIFICANCE: Despite a significant independent main effect of walking velocity, a more unstable postural control observed during traversing of camouflaged versus visible curbs was found not to be walking velocity-related in young individuals. Further research, including elderly may shed more light on these results.

Copyright © 2019 Elsevier B.V. All rights reserved.

Language: en

Keywords

Curb negotiation; Margin of stability; Postural control; Uneven walking; Velocity