title: Does knee awareness differ between different knee arthroplasty prostheses? A matched, case-control, cross-sectional study.
abstract: BACKGROUND
  Low knee awareness after Total Knee Arthroplasty (TKA) has become the ultimate goal in trying to achieve a natural feeling knee that meet patient expectations. To accommodate this manufacturers of TKAs have developed new prosthetic designs that potentially could give patients a more natural feeling knee during activities. The purpose af this study was to compare the Forgotten Joint Score (FJS) and Oxford Knee Score (OKS) of patients treated with a previous generation standard Cruciate Retaining (CR) TKA to the scores obtained by patients treated with a newer generation CR TKA or a mobile bearing CR TKA.
  
  
  METHODS
  We identified all patients receiving a new generation CR TKA or mobile bearing TKA at our institution between 2010 and 2012. These were matched to a population of patients receiving a standard CR TKA regarding age, gender, year of surgery, Kellgren-Lawrence (KL) grade and pre- and postoperative knee alignment. Patients were asked to complete the FJS and OKS questionnaires. Of the 316 patients completing the survey 64 standard CR TKAs to 35 new generation CR TKAs and 121 standard CR TKAs to 68 mobile bearing TKAs were matched. The FJS and OKS scores of the three TKA designs were compared.
  
  
  RESULTS
  When comparing the new generation CR TKAs to the standard CR TKAs we found statistically significant higher OKS and FJS scores (6 (p = 0.04) and 16 (p = 0.03) points respectively) for the new generation CR TKAs. When comparing the mobile bearing TKAs to the standard CR TKAs we found a statistically significant higher OKS score (3 points, p = 0.04), and a higher but non-significant FJS score (4 points, p = 0.48) for the mobile bearing TKAs.
  
  
  CONCLUSIONS
  Patients receiving the new generation CR TKA obtained higher FJS and OKS scores when compared to patients receiving a standard CR TKA, indicating that the use of this newer prosthetic design facilitate less knee awareness and better function after TKA.
authors.affiliation: Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Kettegård Allé 30, 2650, Hvidovre, Denmark. morten@grovethomsen.dk.
authors.forename: Morten G
authors.initials: MG
authors.lastname: Thomsen
authors.affiliation: Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Kettegård Allé 30, 2650, Hvidovre, Denmark.
authors.forename: Roshan
authors.initials: R
authors.lastname: Latifi
authors.affiliation: Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Kettegård Allé 30, 2650, Hvidovre, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kallemose
authors.affiliation: Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Kettegård Allé 30, 2650, Hvidovre, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Husted
authors.affiliation: Department of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Kettegård Allé 30, 2650, Hvidovre, Denmark.
authors.forename: Anders
authors.initials: A
authors.lastname: Troelsen
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000295:instrumentation*; D001364:Awareness; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011474:Prosthesis Design; D020127:Recovery of Function; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
keywords: Arthroplasty; Awareness; Design; FJS; Knee; OKS; Rehabilitation; TKA