関節リウマチに対する膝蓋骨非形成を伴わない人工膝関節全置換術の長期予後

Whether to resurface the patella in total knee arthroplasty for patients with rheumatoid arthritis remains controversial. This study evaluated long-term clinical and radiographic outcomes after total knee arthroplasty without patellar resurfacing.

Of 100 knees in 74 patients who underwent total knee arthroplasty without patellar resurfacing, 64 knees in 49 patients were available for follow-up (mean, 13.6 years). Clinical evaluations included the presence of anterior knee pain at final follow-up, Knee Society Score, Knee Society Functional Score and Kujala score. Plain radiographic evaluations assessed patellar thinning and its relationship with clinical outcomes. We also compared outcomes between remission and non-remission groups based on Disease Activity Score in 28 joints using C-reactive protein at final follow-up.

The incidence of anterior knee pain was 9.3%. At follow-up, Knee Society Scores and Functional Scores had improved significantly (p < 0.05). Although patellar thinning progressed, it did not appear to affect clinical outcomes or incidence of anterior knee pain. Disease activity did not differ significantly between groups or by presence of anterior knee pain.

Long-term outcomes of total knee arthroplasty without patellar resurfacing in rheumatoid arthritis were favourable, indicating that this approach is acceptable.