title: Weight change following knee and hip joint arthroplasty-a six-month prospective study of adults with osteoarthritis.
abstract: BACKGROUND
  Inconsistent findings of weight change following total knee (TKA) and hip (THA) arthroplasty may largely be attributable to heterogeneous cohorts and varied definitions of weight loss. This study examined weight change following TKA and THA for osteoarthritis (OA).
  
  
  METHODS
  64 participants with hip or knee OA were recruited from orthopaedic joint arthroplasty waiting lists at a single major Australian public hospital between March and October 2011. The Short Form (SF) 12 survey was used to assess baseline physical and mental functioning. 49 participants completed 6 month follow-up (20 from the THA group and 29 from the TKA group).
  
  
  RESULTS
  The majority of subjects lost weight (>0 kg) 6 months following THA (70 %) and TKA (58.6 %). When at least a 5 % reduction in total body weight was used to define clinically significant weight loss, the proportion of people with weight loss was 37.9 % for TKA and 25 % for THA. Greater weight loss occurred 6 months following TKA compared with THA (7.2 % versus 3.7 % of body weight; p = 0.04). Worse pre-operative physical functioning (SF-12) was associated with greater weight loss following TKA (β = 0.22 kg, 95 % CI 0.02-0.42 kg; p = 0.04).
  
  
  CONCLUSIONS
  Most people lost weight (>0 kg) 6 months following TKA and THA and a considerable proportion of people achieved ≥5 % loss of body weight. The magnitude of weight loss was greater following TKA than THA, with worse pre-operative function being a predictor of more weight loss. Further attention to weight management is required to assist a greater number of people to achieve a larger magnitude of weight loss following knee and hip joint arthroplasty.
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, VIC, 3004, Australia. andrew.teichtahl@monash.edu.|Baker IDI Heart and Diabetes Institute, Commercial Road, Melbourne, VIC, 3004, Australia. andrew.teichtahl@monash.edu.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Teichtahl
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, VIC, 3004, Australia. elqui2@student.monash.edu.
authors.forename: Emma
authors.initials: E
authors.lastname: Quirk
authors.affiliation: Department of Physiotherapy, Alfred Hospital, Melbourne, VIC, 3004, Australia. p.harding@alfred.org.au.|Department of Physiotherapy, Centre for Health, Exercise and Sports Medicine, School of Health Sciences, University of Melbourne, Victoria, Australia. p.harding@alfred.org.au.
authors.forename: Paula
authors.initials: P
authors.lastname: Harding
authors.affiliation: Department of Physiotherapy, Alfred Hospital, Melbourne, VIC, 3004, Australia. a.holland@alfred.org.au.|Department of Physiotherapy, La Trobe University, Melbourne, Vic, Australia. a.holland@alfred.org.au.
authors.forename: Anne E
authors.initials: AE
authors.lastname: Holland
authors.affiliation: School of Health Sciences, University of Melbourne, Victoria, Australia. c.delany@unimelb.edu.au.
authors.forename: Clare
authors.initials: C
authors.lastname: Delany
authors.affiliation: Department of Physiotherapy, Centre for Health, Exercise and Sports Medicine, School of Health Sciences, University of Melbourne, Victoria, Australia. ranash@unimelb.edu.au.
authors.forename: Rana S
authors.initials: RS
authors.lastname: Hinman
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, VIC, 3004, Australia. anita.wluka@monash.educ.
authors.forename: Anita E
authors.initials: AE
authors.lastname: Wluka
authors.affiliation: Department of Orthopaedic Surgery, Alfred Hospital, Melbourne, VIC, 3004, Australia. s.liew@alfred.org.au.|Department of Surgery, Monash University, Melbourne, Australia. s.liew@alfred.org.au.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Liew
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Alfred Hospital, Melbourne, VIC, 3004, Australia. Flavia.cicuttini@monash.edu.
authors.forename: Flavia M
authors.initials: FM
authors.lastname: Cicuttini
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip; D019645:Arthroplasty, Replacement, Knee; D001696:Biomechanical Phenomena; D005260:Female; D006621:Hip Joint / Q000503:physiopathology / Q000601:surgery*; D006779:Hospitals, Public; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D015207:Osteoarthritis, Hip / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D011446:Prospective Studies; D020127:Recovery of Function; D013997:Time Factors; D016896:Treatment Outcome; D014739:Victoria; D015431:Weight Loss