title: Does bariatric surgery prior to total hip or knee arthroplasty reduce post-operative complications and improve clinical outcomes for obese patients? Systematic review and meta-analysis.
abstract: OBJECTIVE
  Our aim was to determine whether, based on the current literature, bariatric surgery prior to total hip (THA) or total knee arthroplasty (TKA) reduces the complication rates and improves the outcome following arthroplasty in obese patients.
  
  
  METHODS
  A systematic literature search was undertaken of published and unpublished databases on the 5 November 2015. All papers reporting studies comparing obese patients who had undergone bariatric surgery prior to arthroplasty, or not, were included. Each study was assessed using the Downs and Black appraisal tool. A meta-analysis of risk ratios (RR) and 95% confidence intervals (CI) was performed to determine the incidence of complications including wound infection, deep vein thrombosis (DVT), pulmonary embolism (PE), revision surgery and mortality.
  
  
  RESULTS
  From 156 potential studies, five were considered to be eligible for inclusion in the study. A total of 23 348 patients (657 who had undergone bariatric surgery, 22 691 who had not) were analysed. The evidence-base was moderate in quality. There was no statistically significant difference in outcomes such as superficial wound infection (relative risk (RR) 1.88; 95% confidence interval (CI) 0.95 to 0.37), deep wound infection (RR 1.04; 95% CI 0.65 to 1.66), DVT (RR 0.57; 95% CI 0.13 to 2.44), PE (RR 0.51; 95% CI 0.03 to 8.26), revision surgery (RR 1.24; 95% CI 0.75 to 2.05) or mortality (RR 1.25; 95% CI 0.16 to 9.89) between the two groups.
  
  
  CONCLUSIONS
  For most peri-operative outcomes, bariatric surgery prior to THA or TKA does not significantly reduce the complication rates or improve the clinical outcome. This study questions the previous belief that bariatric surgery prior to arthroplasty may improve the clinical outcomes for patients who are obese or morbidly obese. This finding is based on moderate quality evidence. Cite this article: Bone Joint J 2016;98-B:1160-6.
authors: University of East Anglia, Norwich, UK.
authors: T O
authors: TO
authors: Smith
authors: Norfolk and Norwich University Hospital, Norwich, UK.
authors: T
authors: T
authors: Aboelmagd
authors: St George's University Hospitals NHS Foundation Trust, London, UK.
authors: C B
authors: CB
authors: Hing
authors: University of East Anglia, Norwich, UK.
authors: A
authors: A
authors: MacGregor
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects* / Q000379:methods; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000379:methods; D050110:Bariatric Surgery / Q000379:methods*; D015992:Body Mass Index; D018849:Controlled Clinical Trials as Topic; D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D009767:Obesity, Morbid / Q000150:complications / Q000601:surgery*; D011183:Postoperative Complications / Q000517:prevention & control*; D011379:Prognosis; D011475:Prosthesis Failure; D012086:Reoperation / Q000706:statistics & numerical data; D018570:Risk Assessment; D016896:Treatment Outcome
keywords: Function; Gastric band; Gastric bypass; Joint replacement; Obesity; Wound