Survival after total joint arthroplasty in patients with rheumatoid arthritis. Comparison of the postoperative life expectancies and survival by initial operative years: 1970s and 1980s group versus 1990s group

A total of 867 patients with rheumatoid arthritis (RA) underwent 1764 total joint arthroplasties (total hip arthroplasty and/or total knee arthroplasty) over three decades from 1970 to 1999. A survey on their postoperative survival was conducted in December 2000 in which these patients were divided into two groups. The patients who had their initial arthroplasty in the period 1970 to 1989 were classified as the “70s and 80s group,” and those who had their initial arthroplasty from 1990 to 1999 were classified as the “90s group.” Using the Kaplan–Meier method, their cumulative survival rates were compared. The survival rates of the 70s and 80s group, consisting of 433 patients, were 84.8% at the 5th postoperative year, 60.1% at the 10th year, and 45.3% at the 15th year. Although the survey period of the 90s group is shorter than that of the 70s and 80s group, their survival rates were 90.2% at the 5th year and 84.3% at the 10th year. At present, the life expectancies of the 90s group are good, and their cumulative survival rate is significantly greater than that of the 70s and 80s group (P < 0.01). It seems that this improvement has been contributed to by the recent increase in the number of RA patients with good prognoses and the well-timed application of arthroplasty, which decreases the number of patients with poor risk.