Which joints are commonly affected in Rheumatoid Arthritis?
The joints most commonly involved at onset are the MCPs, PIPs, wrists, and metatarsophalangeal joints (MTPs). Larger joints generally become symptomatic after small joints. Patients may start out with only a few joints involved (oligoarticular onset) but progress to involvement of multiple joints (polyarticular) in a symmetric distribution within a few weeks to months. Of note, most of the descriptions of RA presentation were made during an era where initial diagnosis was made months to years after the onset of symptoms. As health-care systems are identifying individuals with RA earlier in the disease course through more widespread testing of autoantibodies, it may be that the joints understood to be first involved in RA will change.