Background Patellar resurfacing in total knee arthroplasty (TKA) remains controversial. However, a number of authors have recommended routine patellar resurfacing of patella in patients with rheumatoid arthritis.
Objectives To investigate whether patellar resurfacing in TKA is appropriate in patients with rheumatoid arthritis.
Methods A total of 20 primary TKAs without a resurfacing patella were studied in 14 patients with rheumatoid arthritis. TKAs were performed at our institution between January 2000 and December 2007. All patients were females, and the mean age at the time of surgery was 65.5 years (range 51–74 years). The mean follow-up period after surgery was 7.0 years (range 4–10 years). The components Nexgen LPS-flex (Zimmer), Advance (Wright Medical), Scorpio PS (Stryker Orthopedics) and Vanguard PS (Biomet) were used in 7, 7, 4 and 2 knees, respectively. Clinical assessments after surgery were evaluated by a Knee Society score and patella-specific questions at all intervals. Questions included the presence of anterior knee pain, the relationship of pain with stair climbing and arising from a chair and the presence of patellar crepitus. Radiological evaluations were performed immediately after the surgery and at the time of follow-up examination.
Results The mean knee score was 82.5 ± 11.6 (range 52–100) and the mean function score was 55.9 ± 31.6 (range 0–100) at follow-up. The rate of occurrence of anterior knee pain was 5% (1 case) and that of rising from a chair or stair climbing was 10% (2 cases) at follow-up. During the follow-up period, no patient underwent revision surgery for symptoms related to the patellofemoral joint. Radiographic evaluations are displayed in Table 1.
Conclusions For the rheumatoid arthritis, patellar resurfacing was recommended at the time of TKA 1, 2). However, few studies report highly satisfactory results in terms of pain relief and function in rheumatoid arthritis and recommended non-resurfacing TKA to avoid the potential complications associated with prosthetic patellar replacement3,4). In this study, there was no change in patellar thickness and congruencies with time, and no patient underwent revision surgery for symptoms related to the patellofemoral joint. A non-resurfacing patella in TKA for rheumatoid arthritis could obtain good mid-term results. However, patellofemoral joint space narrowing progressed significantly; therefore, further study on long-term results is essential.
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Disclosure of Interest None Declared