[Physiopathology and therapy of localized osteopenia].

Osteopenia is a condition of reduced bone mineral content including osteoporosis, characterised by a reduced bone mass but normal mineral composition of bone tissue, and osteomalacia, characterised by unchanged bone mass but a deficient level of calcification of the protein matrix. Both conditions possess multifactorial etiopathogeneses and may affect the skeleton as a generalised or local manner, thus creating syndromes of circumscribed osteomalacia (osteomalacia of the patella, of the jaw). In some cases of local osteopenia, genetic, ethnic, dietary (inadequate intake of calcium, vitamin D), behavioural (abuse of smoking, coffee or alcohol), mechanical (reduced muscular exercise) and jatrogenic factors can play an important pathogenetic role. The definition of the exact nature of osteopenia (osteoporosis or osteomalacia), now possible using instrumental and laboratory tests, and the identification of the pathogenetic factors involved enable a correct therapy to be commenced.