{'fraction_non_alphanumeric': 0.04342507645259939, 'fraction_numerical': 0.047706422018348627, 'mean_word_length': 4.527027027027027, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Correlation of body growth and bone mineral density measured by ultrasound densitometry of the calcaneus in children and adolescents.

The assessment of growth, including the developmental change in bone mass, is crucial for child health care. We herein report normative values of bone mineral density (BMD) for calcaneus obtained from a large cross-section sample in Japanese school children. To investigate yearly physical growth from pre-school age to adulthood, we measured height, weight, body mass index (BMI), and BMD in 3,835 school children aged 3 to 18 (1,886 boys and 1,949 girls). Participating institutions included kindergarten, junior high schools, high schools, and a college of technology. The growth pattern (or velocity) of BMD (the ratio of trabecular bone area of the calcaneum) shows 3 phases according to the age rage: 3-10, 11-15, and 16-18 years for boys, and 3-7, 8-15, and 16-18 years for girls, both peaking at age 16 years. Likewise, that of weight shows 3 phases: 3-4, 5-15 and 16-18 years for boys, and 3-4, 5-14 and 15-18 years for girls, while the growth pattern of height shows 2 phases: 3-15 and 16-18 years for boys, and 3-13 and 14-18 years for girls, both sexes peaking at approximately 16 years. Therefore, the physical growth pattern of the school children shows progressive growth until 16 years, at which time growth is generally completed. In children under 16 years old, BMD of the calcaneus is higher in girls than in boys. Boys and girls show a similar growth pattern in body height and weight before peak development; however, the physical growth of boys eventually exceeds that of girls.