Impact of Spasticity on Balance Control during Quiet Standing in Persons after Stroke.

Reza Rahimzadeh Khiabani,George Mochizuki,Chris Boulias,William H Gage,Farooq Ismail,Chetan P Phadke

doi:10.1155/2017/6153714

Abstract

Background Balance impairments, falls, and spasticity are common after stroke, but the effect of spasticity on balance control after stroke is not well understood. Methods In this cross-sectional study, twenty-seven participants with stroke were divided into two groups, based on ankle plantar flexor spasticity level. Fifteen individuals with high spasticity (Modified Ashworth Scale (MAS) score of ≥2) and 12 individuals with low spasticity (MAS score <2) completed quiet standing trials with eyes open and closed conditions. Balance control measures included centre of pressure (COP) root mean square (RMS), COP velocity, and COP mean power frequency (MPF) in anterior-posterior and mediolateral (ML) directions. Trunk sway was estimated using a wearable inertial measurement unit to measure trunk angle, trunk velocity, and trunk velocity frequency amplitude in pitch and roll directions. Results The high spasticity group demonstrated greater ML COP velocity, trunk roll velocity, trunk roll velocity frequency amplitude at 3.7 Hz, and trunk roll velocity frequency amplitude at 4.9 Hz, particularly in the eyes closed condition (spasticity by vision interaction). ML COP MPF was greater in the high spasticity group. Conclusion Individuals with high spasticity after stroke demonstrated greater impairment of balance control in the frontal plane, which was exacerbated when vision was removed.

Highlights

Stroke can result in neurological damage of the upper motor neurons (UMNs) leading to spasticity [1], with studies reporting prevalence of poststroke spasticity of up to 43% [2]
The results suggested that individuals with high spasticity had greater balance control challenges during eyes closed conditions in ML centre of pressure (COP) velocity, trunk roll velocity, trunk roll velocity frequency amplitude at 3.7 Hz, and trunk roll velocity frequency amplitude at 4.9 Hz measures (Tables 4 and 5)
Individuals with high spasticity had greater balance control challenges compared to individuals with low spasticity in ML mean power frequency (MPF) measures (Table 4)

Summary

Introduction

Stroke can result in neurological damage of the upper motor neurons (UMNs) leading to spasticity [1], with studies reporting prevalence of poststroke spasticity of up to 43% [2]. A common challenge in persons with stroke is impaired balance control, which affects independence in ADLs [5]. The high spasticity group demonstrated greater ML COP velocity, trunk roll velocity, trunk roll velocity frequency amplitude at 3.7 Hz, and trunk roll velocity frequency amplitude at 4.9 Hz, in the eyes closed condition (spasticity by vision interaction). Individuals with high spasticity after stroke demonstrated greater impairment of balance control in the frontal plane, which was exacerbated when vision was removed

Methods

Results

Discussion

Conclusion