Recent studies have suggested a decreased need for orthopaedic surgery in patients with rheumatoid arthritis (RA). We analysed trends in total knee replacement (TKR) in RA using TKR in osteoarthritis (OA) as a point of reference.
Data on TKRs from the Finnish Arthroplasty Register and population data from Statistics Finland were used to analyse the trends in TKRs among patients aged = 40 years with primary osteoarthritis (OA) or RA in Finland for the period from 1980 to 2010.
During 1980-2010, the overall incidence of TKRs increased 20-fold from 14.2 to 305.3 operations per 10(5) person-years. After peaking in 1992, the annual incidence of TKRs for RA decreased gradually from 19.6 to 10.8 per 10(5) [incidence rate ratio (IRR) 0.97, p