New York—June 12, 2013
Two new studies by researchers at Hospital for Special Surgery have shed light on joint replacement outcomes in patients with rheumatoid arthritis (RA). One study overturns the common belief that RA patients have worse outcomes after a total knee replacement (TKR) than patients who undergo the operation for osteoarthritis. The other study demonstrates that RA patients who undergo a total hip replacement were as likely to have significant improvements in function and pain as patients with osteoarthritis (OA), even though they did not do as well.
In one study, investigators used the HSS Total Joint Replacement registry to identify 178 rheumatoid arthritis patients and 5,206 osteoarthritis patients who underwent a TKR. Patients with RA were sicker—while 72% of osteoarthritis patients had no comorbidities, only 34% of rheumatoid arthritis patients fell into this category.
Although TKR patients with RA had worse pain and function prior to surgery compared to controls, these differences disappeared after surgery. “In RA patients, their preoperative scores were significantly worse than the osteoarthritis controls, but in fact our knee replacement patients caught up,” said Dr. Goodman. Patients in both groups had similar satisfaction rates.
Investigators also identified 32 RA patients and 342 OA patients who underwent a TKR revision. In this analysis, they discovered that OA and RA patients had similar pain and function pre-operatively, but patients with rheumatoid arthritis actually had significantly less pain, better function, and were much more satisfied at two years. “Our RA patients undergoing knee replacement revisions did better than our osteoarthritis patients,” said Dr. Goodman.