Reference values of bone mineral density of proximal femur for Southeast Asian children and adolescents

Summary Bone mineral density (BMD) of the proximal femur helps evaluate bone density in children with reduced mechanical loading of the lower extremities. This study provides the first reference values of bone mineral density of proximal femur according to age and sex for Southeast Asian children and adolescents. Objectives The study aimed to (1) establish normative data of BMD of the proximal femur (femoral neck and total hip), measured by dual-energy X-ray absorptiometry (DXA), for healthy Thai children aged 5 to 18 years and (2) ascertain the relationships between BMD, growth, and puberty. Methods Proximal femur scans of 170 boys and 191 girls obtained from DXA (Lunar Prodigy Pro, GE, and software enCORE version 7.53) were un-analyzed and then re-analyzed with the upgraded software enCORE version 17 SP2 for BMD assessment. The bone mineral apparent density of the femoral neck (FNBMAD) was calculated. Results Sex and Tanner stage-specific BMD normative data were generated. BMD values of the femoral neck and total hip increased with age and pubertal progression. FNBMAD values were not markedly influenced by age and puberty. Using multiple linear regression analysis, age and weight affected FNBMD and total hip BMD in boys and girls, but height and Tanner stage only influenced girls. Age did not significantly influence FNBMAD in either sex. Tanner stage weakly influenced FNBMAD only in boys. Conclusions We established normative reference data for BMD of the proximal femur measured by DXA in Thai children aged 5 to 18 years. Our reference data will help clinicians and researchers assess and interpret the BMD of the proximal femur for Southeast Asian children.