Paretic propulsion changes with handrail Use in individuals post-stroke

Abstract

Background: Roughly 800,000 people experience a stroke every year in the United States, and about 30% of people require walking assistance (walker, cane, etc.) after a stroke. Gait training on a treadmill is a common rehabilitation activity for individuals post-stroke and handrails are typically used to assist with walking during this training, however individual interaction with these handrails are not usually considered and quantitatively reported. Individuals may exert force onto the handrails to aid with propulsive force, but the relationship between limb propulsive force and handrail propulsive force are not known.

Research question: How do individuals post-stroke alter paretic propulsive force when using an assistive device, such as handrails on a treadmill?

Methods: Twenty-one individuals post-stroke (eight current assistive device users and thirteen individuals who do not use an assistive device) walked on a treadmill for 3 min during three conditions: no handrail use, light handrail use (<5% BW) and self-selected handrail use. Three multilevel models were used to compare percent handrail, paretic and nonparetic propulsion between handrail conditions and assistive device groups.

Results: The handrail propulsive impulse was more during the self-selected handrail condition compared to the light handrail condition (p = 0.002). The assistive device use group and the handrail condition fixed effects significantly improved the model fit for paretic propulsive impulse (p = 0.01). The interaction between assistive device use group and handrail condition significantly improved the model fit for nonparetic propulsive impulse (p < 0.001).

Significance: These results suggest that handrail use may impact paretic propulsive impulse. Our initial results suggest that if the goal of rehabilitation treadmill training is to increase the paretic propulsive impulse, having the clinician encourage walking with the handrails may be optimal to promote paretic propulsion.

Keywords: Assistive device; Handrail force; Hemiparesis; Propulsion; Treadmill.

Fig. 1

Anterior Handrail Force. The time series of the anterior handrail force across the paretic stance phase (paretic heel strike to paretic toe-off). The dashed line is the light handrail condition (<5% BW) and the solid line is the self-selected handrail condition. A participant who currently does not use an assistive device is on the left (walking speed = 0.95 m/s) and a participant who currently uses an assistive device is on the right (walking speed = 0.25 m/s).

Fig. 2

Percent Propulsion. (A) The model generated means for handrail propulsive impulse, (B) paretic propulsive impulse, and (C) nonparetic propulsive impulse for each handrail condition, no handrail (NHR), light handrail condition (LHR) and self-selected handrail condition (SSHR). Error bars are standard error and points are individual participants' data points, with blue dots representing the current assistive device users and red dots representing the individuals who currently do not use assistive devices. For handrail impulse and paretic impulse, the current assistive device and individuals who currently do not use an assistive device are combined due to non-significant effects between groups. *p < 0.05 (D) Pie graphs for a representative participant from both the current AD user group and no assistive device group. The values are percent of paretic, nonparetic or handrail to total propulsion, with the no handrail (NHR) condition being on the left, light handrail force (LHR) condition being in the middle and the self-selected handrail force (SSHR) on the right.