Paretic Propulsion and Trailing Limb Angle Are Key Determinants of Long-Distance Walking Function After Stroke.
BACKGROUND
Elucidation of the relative importance of commonly targeted biomechanical variables to poststroke long-distance walking function would facilitate optimal intervention design.


OBJECTIVE
To determine the relative contribution of variables from 3 biomechanical constructs to poststroke long-distance walking function and identify the biomechanical changes underlying posttraining improvements in long-distance walking function.


METHODS
Forty-four individuals >6 months after stroke participated in this study. A subset of these subjects (n = 31) underwent 12 weeks of high-intensity locomotor training. Cross-sectional (pretraining) and longitudinal (posttraining change) regression quantified the relationships between poststroke long-distance walking function, as measured via the 6-Minute Walk Test (6MWT), and walking biomechanics. Biomechanical variables were organized into stance phase (paretic propulsion and trailing limb angle), swing phase (paretic ankle dorsiflexion and knee flexion), and symmetry (step length and swing time) constructs.


RESULTS
Pretraining, all variables correlated with 6MWT distance (rs = .39 to .75, Ps < .05); however, only propulsion (Prop) and trailing limb angle (TLA) independently predicted 6MWT distance, R(2) = .655, F(6, 36) = 11.38, P < .001. Interestingly, only ΔProp predicted Δ6MWT; however, pretraining Prop, pretraining TLA, and ΔTLA moderated this relationship (moderation model R(2)s = .383, .468, .289, respectively).


CONCLUSIONS
The paretic limb's ability to generate propulsion during walking is a critical determinant of long-distance walking function after stroke. This finding supports the development of poststroke interventions that target deficits in propulsion and trailing limb angle.
University of Delaware, Newark, DE, USA.
Louis N
LN
Awad
University of Delaware, Newark, DE, USA.
Stuart A
SA
Binder-Macleod
University of Delaware, Newark, DE, USA.
Ryan T
RT
Pohlig
University of Delaware, Newark, DE, USA dreisman@udel.edu.
Darcy S
DS
Reisman
D001696:Biomechanical Phenomena; D003430:Cross-Sectional Studies; D005080:Exercise Test; D005260:Female; D006801:Humans; D007866:Leg / Q000503:physiopathology*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010291:Paresis / Q000209:etiology / Q000503:physiopathology* / Q000534:rehabilitation*; D012044:Regression Analysis; D020521:Stroke / Q000150:complications / Q000503:physiopathology*; D000071939:Stroke Rehabilitation; D016896:Treatment Outcome; D016138:Walking / Q000502:physiology*
biomechanics; gait; hemiparesis; rehabilitation; stroke; walking