[Nature and significance of osteopenia]

New realisations on the regulation of bone and calcium metabolism by hormones and vitamins, modern methods of the radiologic and morphologico-morphometric diagnostics considerably increased our knowledge about the deminerlising diseases of the skeletal system. The possibilities for diagnostics and therapy resulting from this are restricted in practice by a non-adequate nomenclature. The introduction of the disease group notion "osteopenia" for all demineralising processes and its definition as well as the representation of the differential diagnostics of osteolamacia, fibrosteoclasia and syndrome of osteoporosis as clinical main representatives of osteopenia shall help to prevent diagnostic and therapeutic errors.