Quantitative computed tomography and computed tomography in children.

Quantitative computed tomography (QCT) methodologies have been instrumental in deepening our understanding of bone acquisition and strength during childhood. Important publications in the last year have drawn attention to the functional muscle-bone unit, showing that factors such as population ancestry, bone size, and muscle composition are additional dimensions of bone strength that affect muscle-bone relationships. The role of adiposity in pediatric bone health is complex and may vary by sex, puberty stage, and degree of obesity. Several new studies have demonstrated the association of peripheral QCT (pQCT) outcomes with fracture, although pQCT outcomes are not superior to dual-energy x-ray absorptiometry measures in this regard. New high-resolution pQCT studies document transient weakness in mid-puberty that coincides developmentally with the period of peak fracture incidence. These new studies will ultimately help us understand the development of sex differences in bone strength that emerge in adolescence.