Silvia Hayer, Kurt Redlich, Adelheid Korb, Sonja Hermann, Josef Smolen, Georg Schett
The objective of this study was to determine the nature of the initial changes of joint inflammation occurring before, at the time of, and shortly after onset of clinically apparent arthritis. Infiltration of the tendon sheaths by granulocytes and macrophages as well as formation of osteoclasts next to the inflamed tendon sheaths were the first pathologic events. Tenosynovitis rapidly led to remodeling of the sheaths into pannus-like tissue, which formed osteoclasts that invaded the adjacent mineralized cartilage. In contrast, absence of osteoclasts led to uncoupling of tenosynovitis from invasion into cartilage and bone. Structural damage begins even before the onset of clinical symptoms of arthritis and involves the tendon sheaths as well as adjacent cartilage and bone. These results suggest that tenosynovitis is an initiating feature of arthritis and that joint destruction starts right from the onset of disease. The authors conclude that the findings thus underscore the importance of immediate initiation of an effective therapy in patients with inflammatory arthritis.
Arthritis and Rheumatism, Volume 56, Issue 1 , Pages 79 – 88