Bone quantity and quality in Brazilian female schoolchildren and adolescents.

The aim of the present study was to evaluate quantitative ultrasound parameters of the finger phalanges bones (AD-SoS, amplitude-dependent speed of sound, and BTT, bone transmission time) of schoolchildren, using a DBM Sonic device (IGEA, Carpi, Italy), to obtain normative values for the Brazilian population. The sample consisted of 1,775 healthy schoolchildren, all females, aged 8-17 years. We observed a progressive increase for the variables of weight, height, body mass index (BMI), AD-SoS, and BTT with advancing age. Results for AD-SoS showed increasing and significant variation from 8 to 17 years old (1,938-2,103 m/s, an increase of 8.52%, P < 0.0001), and also for BTT (0.84-1.45 micros, an increase of 72.6%, P < 0.0001). A gradual increase in the values of AD-SoS and BTT was observed with advances in pubertal stages. There was an interaction between the variables of age, height, and pubertal stages, predicting AD-SoS (R (2) = 0.49) and BTT (R (2) = 0.53). The study showed that AD-SoS and BTT, evaluated by means of bone ultrasonometry of the phalanges in females, increase gradually with age, being more evident during puberty, probably as a reflex of the structural organization of bone growth and development, or changes in the content of the bone tissue.