The Feasibility of Lateral Externally-Induced Perturbation Training in Fall Prevention after Stroke

Background: Many balance and falls interventions mainly focus on training with voluntarily initiated movements. External perturbation training may be necessary for reducing falls since falls are equally likely to occur from either. Objectives: To determine the effects and generalizability of lateral perturbation training on paretic limb stepping after stroke. Whether sensorimotor impairments impact the ability to initiate paretic leg steps. Methods: Seventeen individuals >6 months post-stroke participated in a 6-week lateral perturbation training. Percent of paretic leg first steps and step type before and after training during the lateral treadmill and lateral waist-pull perturbation were recorded. Motor recovery and paretic foot cutaneous sensation were assessed. Results: Twelve participants (9 male/ 3 female) were recruited from a stroke registry with a mean age of 63.4 years (range 54-72) and completed treadmill perturbation training. They increased the percent of paretic leg steps. After training, fewer medial steps were taken during treadmill perturbations (P<0.02), translating to more lateral steps (P=0.04) and fewer medial steps (P=0.01) during the waist-pull perturbation. Significant correlations were found between foot cutaneous sensation and paretic steps taken during the treadmill perturbation (rs=-0.70, P=0.01) and motor recovery (rs=0.75, P=0.005) and paretic steps taken during the waist-pull perturbation. Conclusions: Transitioning from medial to lateral steps may be a more effective balance recovery strategy. Although, sensorimotor impairments may limit stepping with the paretic leg.