title: Mid-term Results of Total Knee Arthroplasty Using PFC Sigma RP-F.
abstract: OBJECTIVE
  We compared the mid-term results after total knee arthroplasty (TKA) using PFC Sigma RP-F mobile model with PFC Sigma PS fixed model.
  
  
  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°) was greater than that in the control group (125°) 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.
authors.affiliation: Department of Orthopaedic Surgery, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Jun-Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Sang-Ho
authors.initials: SH
authors.lastname: Cheon
authors.forename: Hee-Soo
authors.initials: HS
authors.lastname: Kyung