[Irreversible loss of the substantia compacta in metabolic bone diseases based on roentgenogrammetric data]

A study was made of gram roentgenographic indices of the compact substance (CS) in metabolic skeletal diseases: of the cortical layer summary thickness (CST) and a cortical area (CA) of the metacarpal bone II in 310 patients and the femoral cortical index (FCI) in 184 patients. Three components in CS loss were singled out: involution, metabolic and inert. Irreversibility of endocortical loss of the osseous tissue was shown and interpreted as fast developing involution osteoporosis. CST is a more sensitive index of CS loss than FCI though the combination of both indices provides more information on CS loss.