Turns while walking among individuals with Parkinson's disease following overground locomotor training: A pilot study

Background: Individuals with Parkinson's disease are challenged in making turns while walking, evidenced by reduced intersegmental coordination and reduced dynamic postural stability. Although overground locomotor training previously improved ambulation among people with Parkinson's disease, its effect on walking turns remained unknown. We sought to understand the effects of overground locomotor training on walking turns among individuals with mild-Parkinson's disease. Methods: Twelve participants with Parkinson's (7 Males/5 Females; Age: 68.5 ± 6.4 years) completed twenty-four sessions lasting approximately 60 min and over 12–15 weeks. Baseline and follow-up assessments included the ten-minute walk test using wearable sensors. Primary outcomes included changes to intersegmental coordination, measured by peak rotation and normalized peak rotation, and dynamic postural stability, measured by peak turn velocities in the frontal and transverse planes. Statistical analysis included one-tailed paired t-tests and Cohen's d effect sizes with α = 0.05. Findings: No effects of overground locomotor training on mean peak thoracic rotation (+0.23 ± 4.24°; Cohen's d = 0.05; P = 0.45) or mean normalized peak thoracic rotation (−0.59 ± 5.52 (unitless); Cohen's d = 0.10; P = 0.45) were observed. Moderate and small effects of overground locomotor training were observed on mean peak turn velocities in the frontal (+1.59 ± 2.18°/s; Cohen's d = 0.43; P = 0.01) and transverse planes (+0.88 ± 3.18°/s; Cohen's d = 0.25; P = 0.18). Interpretation: This pilot study provides preliminary evidence suggesting that individuals with mild-Parkinson's moderately improved frontal plane dynamic postural stability after overground locomotor training, likely attenuating the perturbations experienced while turning.