title: Obesity has a negative impact on clinical outcome after total knee arthroplasty.
abstract: OBJECTIVE
  Obesity has been linked to the development of osteoarthritis of the knee and since the incidence of obesity is increasing, the need for total knee arthroplasty (TKA) is likely to increase. Conflicting findings have been reported concerning the relationship between obesity and TKA. It has been shown in several studies, that obese patients have poorer clinical results after operation. On the other hand it has also been reported similar results for obese and non-obese patients. The purpose of this study was to analyze clinically and radiologically the results of total knee artrhoplasty in obese patients.
  
  
  METHODS
  The study consisted of 48 patients who had a TKA. The patients were divided in two groups according their body mass index. Patients of BMI over 30 were regarded as obese.
  
  
  RESULTS
  The obese patients had poorer clinical success at the final follow-up, their WOMAC scores were significantly higher compared to non-obese (pain 20.7 vs. 11.6; p = 0.021, stiffness 26.9 vs. 13.4; p = 0.006, physical function 26.5 vs. 14.4; p = 0.003). Differences were also found in the Knee (KS) and Function (FS) scores and a long-term postoperative ROM and (KS: 83.6 vs. 88.9; p = 0.01, FS: 63.6/76.3; p = 0.051, ROM: 104.6 vs. 109.6; p = 0.016). Non-obese patients reached better percentage improvement in the KSS compared to obese patients (KS change + 194.5% vs. + 59.5%, p = 0.03; FS change + 51.5% vs. + 14.9%, p = 0.19).
  
  
  CONCLUSIONS
  Obesity has a negative impact on the outcome of TKA, assessed by patients' clinical function and satisfaction level.
authors.affiliation: University of Eastern Finland, Faculty of Health Sciences, Kuopio, Finland. jaakko.jarvenpaa@fimnet.fi
authors.forename: J
authors.initials: J
authors.lastname: Järvenpää
authors.forename: J
authors.initials: J
authors.lastname: Kettunen
authors.forename: T
authors.initials: T
authors.lastname: Soininvaara
authors.forename: H
authors.initials: H
authors.lastname: Miettinen
authors.forename: H
authors.initials: H
authors.lastname: Kröger
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D015992:Body Mass Index; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D017060:Patient Satisfaction; D011859:Radiography; D020127:Recovery of Function; D016896:Treatment Outcome