Purpose: Quantitative ultrasound (QUS) evaluation of bone is attractive for evaluating skeletal status in adolescents, but its use is limited in the United States due to sparse pediatric reference data. This study evaluated associations between radial and tibial speed of sound (SOS) measurements via QUS and demographic, anthropometric and nutritional variables.
Methods: We enrolled 151 healthy participants, aged 11-26 years, during routine visits to an urban adolescent clinic. SOS measurements were obtained using the Omnisense 7000P (Sunlight Medical Ltd., Tel-Aviv, Israel) and correlated with weight, height, gender, race, sexual maturity rating (SMR), and reported nutritional intake.
Results: The sample was 53% female; aged 17+/- 2.8 years (mean +/- SD); and 48% African-American, 21% Hispanic, and 21% Caucasian. Seventy percent of males and 91% of females had achieved SMR 5; 96% of females were postmenarchal. Males met the recommended daily allowance for calcium intake, on average; the females did not. Both the girls and boys reported consumption of inadequate vitamin D. Intake of neither calcium nor vitamin D was correlated with SOS. Radial and tibial SOS were significantly higher in those with SMR 5 (p < .001) and were moderately correlated with age in both genders (r = .42-.64, p < .001). In multivariate analyses, age was associated with SOS at both sites (p < .0001).
Conclusions: This study provides QUS measurements of the peripheral skeleton among healthy adolescents. QUS measurements followed similar age and pubertal distributions to dual-energy X-ray absorptiometry (DXA) bone density measurements; other variables did not follow expected trends. Further research is needed to clarify what skeletal properties are assessed by this technique. This study adds to accumulating evidence that many adolescents do not consume adequate vitamin D or calcium.