Foot morphology of normal, underweight and overweight children

Objective: Due to the fact that there is a global increase in obesity, knowledge about the impact of obesity on the development of a child's foot is of great importance for orthopaedic and paediatric physicians with regard to prevention, clinical treatment and management. Therefore, the purpose of this study was to investigate the influence of body mass on the development of a child's foot based on a foot type classification. Methods: The feet of 1450 boys and 1437 girls aged 2-14 years were measured using a three-dimensional (3D) foot scanner (Pedus, Human Solutions Inc., Germany) in a bipedal upright position. Twelve relevant 3D foot measures were recorded, as well as the children's age, gender, height and mass. Factor analysis of principal components was used to obtain a smaller number of independent and standardized variables. The variables were used for cluster analysis to classify the children's feet. Results: Five foot types were identified: flat, robust, slender, short and long feet. There were significant differences among foot types with respect to the children's body mass index. Normal weight children displayed an almost equal distribution of all foot types throughout childhood. Flat and robust feet were more common in overweight children, whereas underweight children showed more slender and long feet. Conclusion: The influence of excess, as well as deficient mass could be verified for the comprehensive foot morphology based on a foot type classification. Subsequently, foot discomfort as a result of various musculoskeletal disorders may develop. In turn, this might keep the children from being active and therefore reinforce the risk of developing obesity. However, there is still a lack of information regarding these relationships, which needs to be determined. This knowledge may help prevent orthopaedic foot problems and injuries.