Local Bone Erosion in Arthritis
Only few diseases lead to local resorption of bone. Apart from tumor metastases, various granulomatous diseases (including tuberculosis, sarcoidosis, and histiocytosis) can precipitate local bone erosion. One of the most frequent causes for local bone erosion, however, is arthritis, which involves destruction of juxta-articular bone. This process is a hallmark of rheumatoid arthritis (RA) but it also occurs within the context of other chronic forms of arthritis, particularly in psoriatic arthritis (Figure 1). Determination of bone erosion is almost exclusively based on radiographic findings, because direct assessment of these lesions through biopsy is only rarely practical. The term 'bone erosion' describes loss of mineralized tissue at juxta-articular sites, which is commonly associated with a break in the cortical lining.
Hand radiograph of a patient with rheumatoid arthritis. Imaged is the hand of a patient with advanced rheumatoid arthritis with severe destruction of the joint architecture. Asterisks indicate bone erosion.
Signs of inflammatory bone erosion have been found in skeletal remains of individuals from several Indian tribes in Northern America.[7] Destruction of bone by arthritis was first described more than 100 years ago. These earliest studies used histopathologic examination to investigate areas of structural joint damage.[8] Later, with the development of radiographic imaging, bone erosions could be visualized directly and became not only part of the diagnostic criteria for RA but also a valuable tool for monitoring disease.[9,10] Virtually all clinical studies of anti-inflammatory and immuno-modulatory drugs for the treatment of RA have employed clinical end-points as efficacy measures and radiologic endpoints to define drug effects on structural damage. Importantly, the resorption of mineralized tissue that is evident on conventional radiographs is strongly associated with poor functional outcome in patients with chronic arthritis.[11,12,13] With the ultimate aim being to preserve functional status and joint architecture in RA patients, characterization of early disease has been an important goal in RA research over the past 10 years. It soon became evident that bone erosion starts early in disease and progresses most rapidly during the first year.[14] These findings have fostered the concepts that retardation, arrest, or even repair of structural damage should be considered central goals in the treatment of RA.
Arthritis Res Ther. 2007;9(Supp) © 2007 BioMed Central, Ltd.
Copyright to this article is held by the author(s), licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original citation.
This article is published as part of Arthritis Research & Therapy Volume 9 Supplement 1, 2007: Basic science, rationale, background and future of denosumab: a RANK ligand inhibitor. The full contents of the supplement are available online at https://arthritis-research.com/supplements/9/S1.
Cite this: Erosive Arthritis - Medscape - Jun 29, 2007.
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