Background: The relationship between growth of the foot and other anthropometric parameters during body development until puberty has been scarcely studied. Some studies propose that growth of the foot in length may be an early index of puberty. The objective of this cross-sectional study was to analyze the relationship between the growth of the foot in length and width with other anthropometric parameters, in prepubertal and early pubertal schoolchildren (Tanner stage II). Methods: Using an instrument that was designed and calibrated for this purpose, maximum foot length, width and height were obtained in 1005 schoolchildren. Results: The findings indicate that the age of onset of pubertal foot growth spur was 7-8 years in girls, and 8-9 years in boys. Growth in foot length stabilized in both sexes after 12 years of age. In boys, a strong correlation was found between height and foot length (r = 0.884; p < 0.047), and between body mass index (BMI) and forefoot width at 12 years of age (r = 0.935; p < 0.020). A strong correlation was found between height and forefoot width at 6 years in girls (r = 0.719; p < 0.001), as well as between BMI and metatarsal width in 10 years-old girls (r = 0.812; p <0.001). Conclusions: The average increase in foot length and width that precedes the onset of Tanner's stage II in both girls and boys can be considered as a useful biological indicator of the onset of puberty.
Keywords: adolescents; foot size; growth velocity; height; pubertal onset; puberty.