Citation

Arora T, Musselman KE, Lanovaz J, Linassi G, Arnold C, Milosavljevic S, Oates A. PM R 2019; 11(3): 270-277.

Affiliation

College of Kinesiology, University of Saskatchewan, Saskatchewan, Canada.

Copyright

(Copyright © 2019, American Academy of Physical Medicine and Rehabilitation, Publisher Elsevier Publishing)

DOI

10.1016/j.pmrj.2018.07.012

PMID

30036682

Abstract

BACKGROUND: Ambulatory individuals with incomplete spinal cord injury (iSCI) experience frequent falls suggesting impairments in their balance control. Individuals with iSCI are more stable during normal walking as compared to able-bodied individuals; however, it is not known whether this increased stability helps prevent hazardous slips.

OBJECTIVE: Compare walking stability during normal walking between iSCI and able-bodied individuals, and to study the association between stability during normal walking and the intensity of an unexpected slip perturbation.

DESIGN: Cross-sectional SETTING: University of *********** PARTICIPANTS: Twenty iSCI (15 males; age: M=60.05, SD=17.77 years) and 16 (12 males; age: M=58.92, SD=17.10 years) able-bodied (AB) individuals.

METHODS: Stability measures during unperturbed walking at a self-selected speed were collected from all the participants. Additionally, stability measures were also collected from 10 of the AB participants walking at a slower speed. An unexpected slip perturbation was recorded in all participants during a self-selected speed trial and peak-slip heel velocity post slip was recorded. MAIN OUTCOME MEASUREMENTS: Measures of stability: ankle co-contraction, required coefficient of friction, walking velocity, foot angle, antero-posterior margin of stability, percentage double support, step length and width were compared between - iSCI, AB-self selected, and AB-slow walking groups. Associations between slip intensity, indicated by peak post-slip heel velocity, and stability measures were also examined through correlation analysis.

RESULTS: Individuals with iSCI, walked slower, took shorter steps, and spent a greater percentage of time in double support compared to AB individuals walking at a self-selected pace (p<.01). Slower walking velocity was correlated with slower post-slip velocity in participants with iSCI (p=.01) only.

CONCLUSIONS: Individuals with iSCI walk with greater stability than AB individuals during unperturbed walking due to a lower self-selected speed, which appears to reduce the intensity of an unexpected slip perturbation. LEVEL OF EVIDENCE: Level III.

Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Language: en

Keywords

Spinal cord injury; co-contraction; margin of stability; required coefficient of friction; slip perturbation; walking stability