Lower-extremity strength differences predict activity limitations in people with chronic stroke

Abstract

Background. Body system impairments following stroke have a complex relationship with functional activities. Although gait and balance deficits are well-documented in people after stroke, the overlapping influence of body impairments makes it difficult to prioritize interventions. Objective. This study examined the relationship between prospectively selected measures of body function and structure (body mass index, muscle strength, sensation, and cognition) and activity (gait speed, gait endurance, and functional balance) in people with chronic stroke. Design. This was a cross-sectional, observational study. Methods. Twenty-six individuals with mean (SD) age of 57.6 (11) years and time after stroke of 45.4 (43) months participated. Four variables (body mass index, muscle strength difference between the lower extremities, sensation difference between the lower extremities, and Mini-Mental Status Exam score) were entered into linear regression models for gait speed, Six-Minute Walk Test distance, and Berg Balance Scale score. Results. Lower-extremity strength difference was a significant individual predictor for gait speed, gait endurance, and functional balance. Cognition significantly predicted only gait speed. Limitations. The authors did not include all possible factors in the model that may have influenced gait and balance in these individuals. Conclusions. Strength deficits in the hemiparetic lower extremity should be an important target for clinical interventions to improve function in people with chronic stroke. © 2009 American Physical Therapy Association.