A seronegative, non-nodular arthritis develops in 52 - 85% of cases.
Often proceeding other manifestations of RPC. Most commonly, arthritis is asymmetrical and nonerosive. Although any joint may be affected, the hands, feet, wrists, ankles, knees and spine are often involved. These locations may be migratory and painful. Costochondral joints are often involved with the forefeet are often spared.
Effusions may accompany the arthritis, and serology findings may be non-inflammatory or mildly inflammatory in nature. Acute onset of an inflamed joint may mimic crystal arthropathy. Sed-rates generally remain within the normal ranges.
Although RPC - associated arthritis is usually nonerosive, at least one case of arthritis mutilans has been published in association with RPC.
Other forms of arthritis have been reported in conjunction to RPC and may be a secondary condition.
