Clinical Results of Posterior Cruciate Ligament–Retaining Total Knee Arthroplasty in Patients with Rheumatoid Arthritis: A 5- to 13-Year Follow-up Study

Aim: Total knee arthroplasty (TKA) is commonly performed to relieve pain and improve function in patients with rheumatoid arthritis (RA). However, treatment with posterior cruciate ligament–retaining (CR-type) TKA is thought to be controversial, particularly in patients with RA. In the present study, we aimed to investigate the clinical results of CR-type TKA and evaluate the efficacy of this type of prosthesis in patients with RA. Methods: In our hospital, 77 CR-type TKA procedures were performed in 59 patients with RA between January 2001 and 2008. In total, we assessed 45 CR-type TKA procedures in 30 patients with RA who underwent follow-up for at least 5 years. The assessment was based on the Knee Society clinical score (KSS) and an independent radiographic analysis. Results: During a mean follow-up period of 8 years, 2 patients developed late infection and 2 other patients experienced supracondylar fracture after each TKA procedure. After surgery, the KSS improved significantly among the patients and 87% of the patients did not experience any pain. Moreover, the mean postoperative maximum flexion angle was 114.8°, whereas the maximum extension angle was -4.2°. Conclusion: Although additional long-term follow-up studies are required, the results of our medium-term followup study indicate that CR-type TKA was not problematic, even in patients with RA.