title: Effect of femoro-tibial component size mismatch on outcome in primary total knee replacement.
abstract: BACKGROUND
  Most total knee arthroplasty systems allow a degree of femoro-tibial component size mismatch. We aim to investigate the influence of size mismatch on outcome after primary total knee arthroplasty.
  
  
  METHODS
  We reviewed 332 patients with cruciate-retaining Genesis II total knee arthroplasty with regard to femoro-tibial component size mismatch and Oxford Knee Score (OKS). We evaluated effects of Body Mass Index, gender and patellar procedure. Minimum follow-up is five years. We divided patients into four groups (tibial component larger than femoral component, no mismatch, femoral component one size larger and femoral component two sizes larger than tibial component).
  
  
  RESULTS
  There was no statistically significant difference in OKS between the four groups. Size mismatch did not have a statistical significant effect on OKS in a multivariate analysis. Women had mismatched components in 66% of all cases and men in 40% of all cases.
  
  
  CONCLUSIONS
  Our study showed no statistically significant effect of femoro-tibial size mismatch on outcome after total knee replacement. Compared to men, women tend to have more component size mismatch.
  
  
  METHODS
  Level III, retrospective comparative study.
authors.affiliation: Department of Orthopaedics, West Suffolk Hospital, Hardwick Lane, Bury St. Edmunds, Suffolk IP332QZ, United Kingdom; Department of Orthopaedics, University Hospital Antwerp (UZA), Wilrijkstraat 10, 2650 Edegem, Belgium. Electronic address: heylensteven@yahoo.com.
authors.forename: Steven
authors.initials: S
authors.lastname: Heylen
authors.affiliation: Department of Orthopaedics, West Suffolk Hospital, Hardwick Lane, Bury St. Edmunds, Suffolk IP332QZ, United Kingdom; Department of Orthopaedics, University Hospital Antwerp (UZA), Wilrijkstraat 10, 2650 Edegem, Belgium. Electronic address: knudfoubert@hotmail.com.
authors.forename: Knud
authors.initials: K
authors.lastname: Foubert
authors.affiliation: Monica Orthopaedic Research Institute (MoRe Institute), Stevenslei 20, 2100, Deurne, Antwerp, Belgium; Department of Electrical Energy, Systems and Automation, Ghent University, De Pintelaan 185, 9000 Ghent, Belgium. Electronic address: mvhaver@hotmail.com.
authors.forename: Annemieke
authors.initials: A
authors.lastname: Van Haver
authors.affiliation: Department of Orthopaedics, West Suffolk Hospital, Hardwick Lane, Bury St. Edmunds, Suffolk IP332QZ, United Kingdom. Electronic address: paul.nicolai@wsh.nhs.uk.
authors.forename: Paul
authors.initials: P
authors.lastname: Nicolai
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation*; D005260:Female; D005269:Femur / Q000601:surgery*; D006801:Humans; D007592:Joint Diseases / Q000601:surgery*; D007719:Knee Joint / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012737:Sex Factors; D013977:Tibia / Q000601:surgery*
keywords: Component size mismatch; Femoro-tibial component mismatch; Total knee arthroplasty mismatch