[Generalized osteoporosis in chronic polyarthritis--pathomechanisms and treatment approaches].
Juxtaarticular osteoporosis is a typical x-ray symptom of rheumatoid arthritis and is an early radiological criterion of the disease before destructive changes of joints can be seen. A systemic osteoporosis, independent from corticoid treatment, will develop significantly later. Nevertheless both conditions have some pathogenetic mechanisms in common. The risk of generalized osteoporosis in rheumatoid arthritis correlates with the degree of inflammatory activity. Different cytokines originating from the affected joints can be measured in plasma at increased levels and augment osteoclastic activity in bone tissue. During the early phase of disease the best prevention of osteoporosis is therefore adequate suppression of inflammation. Taking into account these mechanisms, corticoid treatment may be osteoprotective. Clinical manifestation of systemic osteoporosis in rheumatic patients depends on bone mass at onset of disease, on the activity of inflammation, and on additional negative effects on bone mass due to corticoids and immobility.