title: Predicting dissatisfaction following total knee arthroplasty in patients under 55 years of age.
abstract: OBJECTIVE
  Risk of revision following total knee arthroplasty (TKA) is higher in patients under 55 years, but little data are reported regarding non-revision outcomes. This study aims to identify predictors of dissatisfaction in these patients.
  
  
  METHODS
  We prospectively assessed 177 TKAs (157 consecutive patients, 99 women, mean age 50 years; 17 to 54) from 2008 to 2013. Age, gender, implant, indication, body mass index (BMI), social deprivation, range of movement, Kellgren-Lawrence (KL) grade of osteoarthritis (OA) and prior knee surgery were recorded. Pre- and post-operative Oxford Knee Score (OKS) as well as Short Form-12 physical (PCS) and mental component scores were obtained. Post-operative range of movement, complications and satisfaction were measured at one year.
  
  
  RESULTS
  Overall, 44 patients with 44 TKAs (24.9%) under 55 years of age were unsure or dissatisfied with their knee. Significant predictors of dissatisfaction on univariate analysis included: KL grade 1/2 OA (59% dissatisfied), poor pre-operative OKS, complications, poor improvements in PCS and OKS and indication (primary OA 19% dissatisfied, previous meniscectomy 41%, multiply operated 42%, other surgery 29%, BMI > 40 kg/m231%, post-traumatic OA 45%, and inflammatory arthropathy 5%). Poor pre-operative OKS, poor improvement in OKS and post-operative stiffness independently predicted dissatisfaction on multivariate analysis.
  
  
  CONCLUSIONS
  Patients receiving TKA younger than 55 years old should be informed about the increased risks of dissatisfaction. Offering TKA in KL 1/2 is questionable, with a dissatisfaction rate of 59%. Cite this article: Bone Joint J 2016;98-B:1625-34.
authors.affiliation: Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh EH16 4SA, UK.
authors.forename: C E H
authors.initials: CE
authors.lastname: Scott
authors.affiliation: Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh EH16 4SA, UK.
authors.forename: W M
authors.initials: WM
authors.lastname: Oliver
authors.affiliation: Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh EH16 4SA, UK.
authors.forename: D
authors.initials: D
authors.lastname: MacDonald
authors.affiliation: Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh EH16 4SA, UK.
authors.forename: F A
authors.initials: FA
authors.lastname: Wade
authors.affiliation: Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh EH16 4SA, UK.
authors.forename: M
authors.initials: M
authors.lastname: Moran
authors.affiliation: Royal Infirmary of Edinburgh, 51 Little France Crescent, Old Dalkeith Road, Edinburgh EH16 4SA, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Breusch
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000379:methods / Q000534:rehabilitation*; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000503:physiopathology; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D017060:Patient Satisfaction / Q000706:statistics & numerical data*; D011203:Poverty / Q000706:statistics & numerical data; D011379:Prognosis; D011446:Prospective Studies; D011474:Prosthesis Design; D011859:Radiography; D016059:Range of Motion, Articular; D020127:Recovery of Function; D012307:Risk Factors; D012720:Severity of Illness Index; D016896:Treatment Outcome; D055815:Young Adult
keywords: Patient reported-outcome measures; Patient satisfaction; Total knee arthroplasty; Young patients