The assessment of bone mineral mass during growth, periods diseases or therapy which modify bone mineralization in the child is of great interest. Single-photon absorptiometry carried out on forearm bones informs on the mineral density of the compact bone of the appendicular skeleton. It is easy to perform in children and infants. Dual-photon absorptiometry appears to be the most accurate for measuring bone mineral content in endocrine and metabolic bone disorders. The low dose of radiation and the non-invasive nature of this high-precision method render it well-adapted and suitable for measuring bone mineralization in childhood.