Contribution of gait analysis to the understanding of motor development

Abstract

Findings from two studies are presented. Both focused on the gait of Australian primary aged children and the information that this fundamental motor skill provides towards understanding the development of motor performance. In study one 87 (47 male, 40 female) children (5 - 9 years) participated. Children were tested using the Movement Assessment Battery for Children (MABC) (Henderson & Sugden, 1996), and the GAITRite walkway system. Gait parameters of the motor impaired and typically developing children were compared. Walking at a self-selected normal pace the motor impaired children did not significantly differ from their typically developing peers. A comparison of the gait parameters across the three age-bands tested (4 - 6, 7 - 8 & 9 - 10 years) showed Cadence and Double support time to differ significantly between the first and second age-bands with Cadence decreasing and double support time increasing with age. The variability of walking velocity and cadence both decreased significantly from age-band 1 to 2. Further a greater percentage of the motor impaired children were classified as overweight according to their BMI. Two important improvements in the experimental design were introduced for the larger second study (n = 218: 102 Male, 116 Female) ranging in age from 5 - 12 years. Firstly, slow and fast walking speeds were added to the normal walking speed condition to increase the task demand. Secondly, performance on the balance component only of the MABC was used as the criterion for impairment in this analysis. Two important improvements in the experimental design were introduced for the larger second study (n = 218: 102 Male, 116 Female) ranging in age from 5 - 12 years. Firstly, slow and fast walking speeds were added to the normal walking speed condition to increase the task demand. Secondly, performance on the balance component only of the MABC was used as the criterion for impairment in this analysis. Developmental trends were most evident for the stride-to-stride gait variability measurements. Specifically, the velocity, cadence, step length and base of support were all significantly more variable in the 11 and 12 year old children in comparison to the young adult group. It was suggested from these findings that the underlying process regulating the sequence of gait was not yet fully mature at age 12. A major aim of this investigation was to identify a simple objective means to measure the motor skills of children. Using a stepwise discriminant analysis walking at the slow speed was shown to be the best discriminator between the balance impaired and non-impaired children. Using only the base of support and cadence variability measures, 72.2 % of cases were correctly predicted. The third research question arose from the findings of study, viz. Do overweight children have impaired balance and coordination during walking? In this study, only a slightly larger percentage of overweight children (34.4%) were classified as motor impaired compared to the normal weight children (29.9%). It was noted that the overweight children walked with a wider base of support and a longer double support time, though they were no more variable than the normal weight children when the stride-to-stride parameters were assessed. Three major conclusions arose from this investigation. (1) children do not exhibit mature control of the walking sequence by age 12. (2) children classified as balance impaired walked with a pattern similar to those of children from a younger age group. (3) Overweight children although adopting a different walking strategy did not exhibit impaired control of the underlying sequence of walking.