Follow up study of footprints of children aged 6 - 7

　　Flatfoot is a common phenomenon in children. There is a noteworthy concern amongst parents for foot arch development of their children. However, existing research has largely ignored the role of arch development. Because of the fact that 90% of individuals are right brain dominant, there is a need to take into account brain dominance when evaluating the flatfoot data. As such, our study focuses on not only the flatfoot data in itself, but also taking into consideration the effects of brain side dominance. In the past, there have been many methods for categorizing flatfoot. However, none have investigated using both feet of individuals while considering brain dominance, foot arch, and physical fitness performance simultaneously. This study seeks to investigate the association foot arch development or deterioration through the use of a longitudinal survey, in order to investigate dominance, flatfoot and three test of physical fitness by controlling the age, gender of the test subjects.
　　This study is a cohort study, using a 1.5 years follow-up of 547 children aged 6-7 years old. The data collected by field researchers included footprints, joint laxity and three tests of physical fitness, including standing long jump, 20-meter dash, and one leg standing balance. Staheli’s arch index (SAI) was computed from the footprints and statistical techniques were employed to establish an association factor.
　　When both feet of subjects are used in the categorization of flatfoot, the result of our findings showed that individuals with flatfoot displayed inferior one leg standing balance performance. The performance of one leg standing balance was also affected by right and left foot dominance, where the left foot performed inferiorly to the right foot in the one leg standing balance task. By controlling age and gender, flatfoot was also found to be associated with BMI. In the longitudinal survey, foot arch development/deterioration was also discovered to be associated with the change of height of the subjects. Moreover, foot arch deterioration was also determined to be associated with weight and BMI of individuals.
　　From the conclusion of our study, there are two major findings. Firstly, for children with flatfoot, extra attention should be placed to their change in height. On the other hand, for non-flatfoot children, emphasis should be placed on changes in their weight, BMI, height, and heelcord. Secondly, in the case of one leg flatfoot, children with non-dominant foot as their flatfoot would tend to show less satisfying result on balance performance. Similarly, children with left flatfoot would also tend to show less satisfying result on the test of standing alone on the bar. However, whether or not this trend is observed in other balance test requires further studies.