Gait characteristics of children with Williams syndrome with impaired visuospatial recognition: a three-dimensional gait analysis study.

Williams syndrome (WS) is a genetically based neurodevelopmental disorder characterized by intellectual disability and impaired visuospatial recognition. The aim of this study was to analyze the gait characteristics of WS children with impaired visuospatial recognition using a three-dimensional gait analysis (3DGA) to clarify the gait adaptation needed to compensate for it. 3DGA was performed in 8 WS children with impaired visuospatial recognition (mean age, 11.8 years) and 9 age-, sex-, height-, and weight-matched controls. Clinical data, fundamental motor tests, and gait variables while walking on a flat surface and walking up a mat were compared between the two groups, and the correlations between variables were analyzed in the WS children. WS children showed impairment of balance function without muscle weakness. In walking on a flat surface, the WS group showed reduced walking speed, short step length, increased variability of step length, increased knee flexion throughout the stance phase, increased horizontal pelvic range of motion (ROM), and a low Gait Deviation Index and a high Gait Profile Score, which are indices of gait quality. In walking up a mat, the WS group showed further reduced walking speed and decreased sagittal hip flexion and ankle dorsiflexion ROM in the swing phase. Impaired balance function was significantly correlated with increased variability of step length and decreased sagittal ankle dorsiflexion ROM in the swing phase. The detailed gait pattern of WS children with impaired visuospatial recognition was presented. These findings show that impaired visuospatial recognition and balance function contribute to gait adaptation.