The Development of Postural control in Children with and without visual impairments

Abstract

The development of postural stability in children with and without visual impairments (VI) was compared. Thirty eight subjects (4- 12 years old) without VI and 12 subjects with VI (5- 12 years) took part. Stability was measured in 4 quiet standing tasks (normal or foam surface, eyes open (EO) or eyes closed (EC)) and by measuring stability limits (SL) in the anterio-posterior (a-p) and lateral (lat) planes. Results for control subjects were compared using Pearson correlation coefficients, analysis of variance, and analysis of covariance (height as the covariate). For quiet standing tasks, outcome parameters were the standard deviation (SO) of the centre of pressure (CP) in the a-p and lat planes, and mean velocity (vel) of CP movements. For the leaning tasks, SL was measured (normalized to the base of support) in the a-p and lat planes, and SL was compared to CP. Individual results for subjects with VI were compared qualitatively to control subjects. For control subjects, stability increased with age. Subjects with VI were less _stable than controls on all outcome parameters. Differences between groups were more apparent as age increased, particularly for EO conditions. This could indicate a slower pattern of development for subjects with VI compared to controls. The groups were different both in the EO and EC conditions, indicating that postural control with EC is not the same as postural control with a VI, and that vision is important to the development of postural control in children.