title: P.F.C Sigma®cruciate retaining fixed-bearing versus mobile-bearing knee arthroplasty: a prospective comparative study with minimum 10-year follow-up.
abstract: OBJECTIVE
  To prospectively compare long-term clinical and radiological outcomes following a cruciate retaining fixed-bearing (FB) and a mobile-bearing (MB) primary total knee replacement (TKR).
  
  
  METHODS
  We prospectively reviewed 113 TKRs in 99 patients (14 bilateral) with a PFC sigma cruciate retaining rotating platform system, at an average follow-up of 11.1 years (range 10-12). Results were contrasted with those from 89 TKRs in 72 patients (17 bilateral) with a PFC sigma cruciate fixed-bearing prosthesis, at an average follow-up of 12.1 years (range 10-14.1). Outcomes collected included pre- and post-operative range of motion, Oxford Knee Scores, complications encountered, as well as radiographical assessments of polyethylene wear.
  
  
  RESULTS
  In the MB group, mean Oxford Knee Scores improved from 16 pre-operatively to 42 at final follow-up. The mean range of motion was 115° (75-130). In the FB group, mean Oxford Knee Scores improved from 16.2 pre-operatively to 42.5 at final follow-up. The mean range of motion was 111.2 (80-135) degrees at final follow-up.
  
  
  CONCLUSIONS
  We failed to elicit an objectively demonstrable clinical difference between the MB- and FB-implanted knees. Similarly, radiological benefits of the MB implants with regard to polyethylene wear were not evident at a minimum 10-year follow-up.
authors.affiliation: The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale and Huddersfield Foundation NHS Trust, Huddersfield, HD3 3EA, UK. osmanriaz@doctors.org.uk.
authors.forename: O
authors.initials: O
authors.lastname: Riaz
authors.affiliation: The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale and Huddersfield Foundation NHS Trust, Huddersfield, HD3 3EA, UK.
authors.forename: A
authors.initials: A
authors.lastname: Aqil
authors.affiliation: The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale and Huddersfield Foundation NHS Trust, Huddersfield, HD3 3EA, UK.
authors.forename: G
authors.initials: G
authors.lastname: Sisodia
authors.affiliation: The West Riding Knee Unit, Huddersfield Royal Infirmary, Calderdale and Huddersfield Foundation NHS Trust, Huddersfield, HD3 3EA, UK.
authors.forename: G
authors.initials: G
authors.lastname: Chakrabarty
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007720:Knee Prosthesis / Q000009:adverse effects; D008875:Middle Aged; D011184:Postoperative Period; D057234:Preoperative Period; D011446:Prospective Studies; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D016059:Range of Motion, Articular
keywords: Fixed-bearing; Long-term outcome; Mobile-bearing; Total knee replacement