Epidemiologic Factors Affecting Plantar Arch Development in Children with Flat Feet

Background: Foot problems are reported by approximately 70% to 80% of adults and 30% of children. One of the most important characteristics affecting its incidence is medial longitudinal arch. Assessing arch height provides valuable information for prescribing appropriate footwear that reduces the consequences of flatfoot. The main goals of this study were to explore epidemiologic factors that affect arch height and to predict arch height in children with flatfoot based on five variables using widely accessible, low-cost tools. Methods: This study examined plantar arch height in 80 children with flatfoot aged 7 to 15 years. The evaluation criteria included low arch height, correct knee and heel position, and correct body symmetry. To measure arch height, the children sat in a chair and placed their feet on level ground. A caliper was used to measure the height between the bottom of the navicular tuberosity and the floor. Using least mean square error scheme, a multivariable model was fitted to the plantar arch height for all of the participants using independent variables, including age, Cole index, sex, place of residence, and physical activity. Results: Arch height increased as age increased in boys and girls in rural and urban areas. A significant increase in arch height occurred in 12- to 15-year-old boys and 10- to 15-year-old girls. In boys, arch height was 30% lower than in girls (P=.05). In children in cities, arch height was lower by 26% than in children in rural areas (P=.05). Arch height increased by 41.8% in inactive boys and by 115.2% in inactive girls in rural areas. It was reduced by 59.4% in boys and by 47.4% in girls as the Cole index increased from 82.2 to 152.0. The suggested model predicted arch height using the child's age, Cole index, sex, place of residence, and physical activity (r > 0.97, error < 0.04 mm [2%], P < .05). Conclusions: Flat feet in children may be affected by age, sex, Cole index, place of residence, and physical activity. The proposed model allows plantar arch heights in children with flat feet to be predicted without the need for sophisticated technology via controlling the child's weight and physical activity for prescribing appropriate footwear. (J Am Podiatr Med Assoc 102(2): 114-121, 2012)