Bilateral asymmetry in the gait deviation index in school-aged children with the trait of developmental coordination disorder

Background: Although previous studies have identified asymmetry in gait parameters in children with developmental coordination disorder (DCD), they have not investigated whether these findings coexist with asymmetry in gait quality, as represented by the gait deviation index (GDI). Research question: This study sought to measure gait symmetry in children with traits of DCD (DCD trait) to elucidate the characteristic gait pattern. Methods: This study included 172 (82 girls, 90 boys) participants with and without DCD trait (age: 6-12 years), as assessed using the Japanese version of the Developmental Coordination Disorder Questionnaire (DCDQ-J), which consists of three subscales. Three-dimensional gait analysis data were obtained during the gait trials. GDI, step length, and step time data were recorded for both the right and left legs, and symmetry ratios were calculated. Results: Participants in the DCD trait group (n = 30) had a significantly lower GDI score (p < 0.0001) and a higher GDI symmetry ratio (p = 0.004) than typically developing children. Furthermore, DCD trait was related to the GDI symmetry ratio (odds ratio, 1.2; p = 0.001; 95 % confidence interval, 1.062-1.289). The control during movement, which was a DCDQ-J subscale, was negatively correlated with the GDI symmetry ratio (r=-0.257, p<0.001). Significance: This study's results lend support to the hypothesis that an increase in the GDI symmetry ratio is associated with the DCD trait. A quantitative assessment of gait performance is important to help identify gait asymmetry, including gait quality, in children with a DCD trait. Children with a DCD trait have a poor ability to control the interaction of lower leg movements, which may cause bilateral asymmetry in gait quality.