Minimal preoperative degenerative arthritis may not predict poor TKA outcome

Although most orthopedic surgeons presume that patients with more severe degenerative osteoarthritis are better candidates for total knee arthroplasty (TKA), few data have compared outcomes based on the extent of radiographic osteoarthritis. The authors tested the hypothesis that patients with minimal radiographic osteoarthritis would have worse outcomes compared with a matched cohort with severe osteoarthritis. The authors identified 29 patients (31 knees) with minimal degenerative changes who underwent TKA between 2000 and 2004. The authors identified a matched cohort with severe osteoarthritis. Mean follow-up was 5 years (range, 2-10 years). Preoperative knee scores were 63 and 59 in patients with minimal osteoarthritis and severe osteoarthritis, respectively. Postoperative knee scores were 89 and 93, respectively. Preoperative function scores were 57 and 56 in patients with minimal osteoarthritis and severe osteoarthritis, respectively. Postoperative function scores increased to 79 and 72, respectively. Of 31 patients in the minimal osteoarthritis group, 26 (84%) had mild or no pain at the time of last follow-up, whereas 5 (16%) had moderate or severe pain. In the group with severe osteoarthritis, 25 of 31 patients (81%) had mild or no pain at the time of last follow-up, whereas 6 (19%) had moderate or severe pain. In the group with minimal osteoarthritis, 6 of 31 knees (19%) had a complication. Only 1 of 31 knees (3.1%) in the matched cohort had a complication. Fewer than 1% of patients undergoing TKA at the authors' institution had minimal preoperative radiographic osteoarthritis. These patients had a higher risk of complications, but similar pain relief, function, and overall satisfaction compared with a matched group with severe arthritis.