Tibial quantitative ultrasound versus whole-body and lumbar spine DXA in a Dutch pediatric and adolescent population

RATIONALE AND OBJECTIVES. TO understand normal bone development, studies in healthy children and adolescents are important. To assess the applicability of tibial quantitative ultrasound measurements (QUS) in children, we performed a study that compared dual-energy x-ray absorptiometry (DXA) of the lumbar spine and whole body with tibial QUS. METHODS. For this study we recruited 146 Dutch children and adolescents, 58 boys (median age, 14.1 years; range, 7.6-23.4 years) and 88 girls (median age, 18.0 years; range, 7.6-23.5 years). Tanner stage, weight, and height were assessed for all participants. Bone mineral density (BMD; g·cm^-2) of the whole body and lumbar spine (L₂-L₄) and bone mineral apparent density (BMAD) of the lumbar spine (g·cm^-3) were assessed by using the Lunar DPXL. For tibial QUS, the Soundscan compact system was used. RESULTS. Both lumbar as well as whole-body BMD showed a strong, significant correlation with tibial QUS in boys and girls: r(total body boys) = 0.81, r(total body girls) = 0.77, r(lumbar spine boys) = 0.79, and r(lumbar spine girls) = 0.72. Lumbar spine BMAD also showed significant correlations with tibial QUS: r(boys) = 0.63 and r(girls) = 0.63 (for all correlations, P < 0.001). CONCLUSIONS. Our study showing strong, significant correlations between DXA and tibial QUS measurements suggests that tibial QUS is a technique that may be applicable in children and adolescents.