[Bone density measurements on growing skeletons and the clinical consequences]

The measurement of bone mineral density (BMD) was established to judge the fracture risk in an individual. The most commonly used densitometric technique DXA is a two-dimensional method and reports BMD (bone mass/projection area), which increases during growth. Bone mineral density (in g/cm(3)), however, is almost stable and does not change with age or height. To analyze the data special pediatric references including data on age, sex and ethnicity are necessary as well as correction for height. Bone forms a unit with muscle. Bone responds to mechanical loading with increase in bone size and therefore adapts to the biomechanical needs. Therefore, interpretation of bone development data requires data on muscle development.The indication for bone mineral density measurement and result reporting should be made by and together with a pediatric specialist. The diagnosis of osteoporosis should not be made based solely on densitometric measurements. History of low trauma fracture is an important aspect for the definition. Besides DXA there exist further methods with advantages and disadvantages.