Mid-term results of total knee arthroplasty using PFC sigma RP-F

Purpose: We compared the mid-term results after total knee arthroplasty (TKA) using PFC Sigma RP-F mobile model with PFC Sigma PS fixed model. Materials and Methods: We analyzed 45 knees that underwent TKA with PFC Sigma RP-Fn (study group) and 45 knees with PFC Sigma PS (control group). The mean follow-up period was 65 months (range, 60-69 months). The evaluation system of the American knee society was used for clinical and radiological assessment. Also, the maximal knee flexion angle was assessed. Results: The mean maximum flexion angle in the study group (135^o) was greater than that in the control group (125^o) at the early post-operation & final follow-up period (p=0.033). The range of motion (ROM) in the study group was recovered earlier at the postoperative 6 months, and ROM gain was improved to a greater extent at the final follow-up period (p=0.039). The knee score and function score and radiographic evaluation were no difference between the two groups (p>0.05) at the final follow-up. The two cases of radiolucency in posterior condyle and medial tibial plateau and one case of patellar elongation were seen in the study group. Conclusions: The PFC Sigma RP-F mobile system appears to facilitate greater maximum flexion angle and ROM gain with two cases of radiolucent line.