SINGLE LIMB BODY WEIGHT SUPPORTED TREADMILL TRAINING.

Abstract

Purpose/Hypothesis: Gait asymmetries, characterized by differences in step length as well as timing, are common deviations seen in people who have had a stroke. Body weight supported treadmill training (BWSTT) has been shown to improve functional walking ability, including gait asymme-try, in individuals post stroke. Despite these improvements, the labor intensive demands of the task limit its use in the clinic. Multiple therapists are often required and controlling gait kinematics is difficult with one therapist. Previous evidence has shown that unilateral walking training may have an effect on bilateral locomotor activity; specifically, altering conditions on one leg may have an effect on bilateral activity. Unilateral training may have the potential to affect gait symmetry following stroke, although application of this training has not been reported. This study investigated the effects of single limb BWSTT in people with chronic stroke who stepped with their unimpaired limb. Stepping with the unimpaired limb may encourage weight-bearing on the impaired extremity and promote symmetrical walking. Hypothesis: Single limb BWSTT will improve step length symmetry in individuals with chronic stroke. Number of Subjects: Six subjects with chronic stroke who demonstrated a 20% step length asymmetry completed the protocol. Materials/Methods: Subjects completed a 20 minute session of unilateral stepping with their unimpaired limb on the treadmill, and the impaired limb held in a stationary position. Subjects walked on the treadmill for 5 minutes at their normal, overground gait velocity and speed was increased by 25% every 5 minutes. Body weight support was determined by the least amount of support tolerated without buckling. Subjects were evaluated using the Berg Balance Scale and Gait Mat II Regis. Gait speed and symmetry during normal and fast walking speeds were obtained at 1 week pre- and post-training. Additionally, spatial-temporal data was collected immediately pre- and 10, 20, and 30 minutes post-training and 24 hours later. Step length asymmetry was calculated as the ratio of impaired to unimpaired limb step length. Results: Increased step length symmetry was observed at 10 minutes post-single limb walking, with increases in gait speed observed up to 30 minutes. Symmetry changes returned to baseline by the following day while improvements in speed lasted until 1 week post training. Changes in fast walking speed were statistically significant (p < .05), and improvements in symmetry were observed (p = 0.11) but not statistically significant. Conclusions: Single limb BWSTT may improve step length symmetry in the chronic stroke population, although more experimentation is required. Clinical Relevance: The initial findings indicate that unilateral training may improve bilateral walking performance in chronic stroke. Single limb BWSTT may have the potential to be used in the clinic to assist in improving gait speed and symmetry. Such therapy may improve the feasibility of performing BWSTT in the clinic while specifically targeting those who demonstrate gait asymmetry.