Rationale for Bone Health Assessment in Childhood and Adolescence

Skeletal health in childhood and adolescence influences the lifetime risk of bone fragility. Peak bone mass (PBM) reached by early adulthood serves at the “bone bank” for life. For this reason, optimizing bone acquisition in the first two decades can help prevent osteoporosis. Genetic factors determine an estimated 60–80 % of variability in PBM; hormones and nutrition, activity, and other modifiable factors account for the remainder. The expected gains in bone mass and size during the critical growing years can be compromised by several heritable or acquired disorders. Recognizing and addressing threats to bone health are essential to reducing the risk of bone fragility. Bone densitometry is a valuable noninvasive means to identify those at greatest risk for fracture. Although several new methods for assessing bone mass and geometry have evolved in recent years, dual energy x-ray absorptiometry (DXA) remains the recommended densitometry device for clinical use in pediatrics. The availability of robust pediatric normative data and creation of expert guidelines for pediatric densitometry have made DXA an even more valuable diagnostic tool. This book will highlight the clinical utility of DXA for pediatrics including the rationale for when and how to employ it. The overarching goal of this book is to serve as a resource for those acquiring, interpreting, reporting, and utilizing densitometry in pediatric patients. The purpose of this chapter is to review the acquisition of PBM in health and disease and briefly summarize the potential and limitation of bone densitometry in monitoring skeletal development in the growing patient.