Focal bone erosions and generalized osteoporosis are common characteristics of rheumatoid arthritis and are important to the development of deformities and physical disability associated with the disease. Recently, it has been recognized that these bone alterations have similar pathogenesis, regulated by osteoclasts, T cells and cytokines that modulate the balance between osteoprotegerin, RANK ligand and RANK. The understanding of the mechanisms that regulate the recruitment and activation of the osteoclasts to the site of bone lesions in rheumatoid arthritis will clarify the potential of inhibition of bone resorption caused by drugs that interfere with proinflammatory cytokines and with the balance of osteoprotegerin, RANK ligand and RANK. The authors not just discuss the treatment of osteoporosis in rheumatoid arthritis, but review the pathogenesis of the focal erosive bone lesions and osteoporosis in this disease.
osteoporosis; rheumatoid arthritis; RANK ligand; RANK; osteoprotegerin; bone erosion
