Bone remodeling and osteophyte formation after remission of rheumatoid arthritis

Bone remodeling and osteophyte formation rarely take place in active rheumatoid arthritis (RA). To determine if disease inactivation leads to their occurrence, we studied 38 patients with RA whose disease had gone into drug induced remission. We looked for osteophytes at the metacarpophalangeal (MCP) joints in roentgenograms taken before and after remission, and correlated their presence to that of osteoarthritis of the distal interphalangeal (DIP) joints. There were 21 patients with RA who had a median of 3 (range 1-8) osteophytes in their "remission" films which were rarely present in their "activity" films (p less than 0.0001). The osteophytes were frequently symmetrical and most often located (41%) at the third MCP joint. In addition, we observed a peculiar remodeling of the styloid process in 13 patients, 9 of whom had developed MCP joint osteophytes. There were no other detectable differences between patients who had MCP joint osteophytes and those who did not. Presence of osteoarthritis at the DIP joints did not correlate with development of osteophytes. We were able to classify the MCP osteophytes into 3 types on the basis of their shape: hook-like that were most frequently bilateral and situated on the radial aspect of the metacarpal side of the joint, beak-like that were most often found at the ulnar aspect of the phalangeal side, and nipple-like which occurred equally on either sites. These differences in distribution indicate that they are not stages of the same process. Our findings indicate that paraarticular bone remodeling occurs upon remission of RA, even in joints where osteoarthritis is unusual. Its shape and location may depend on both their site and the mechanism of joint damage.