title: Obesity in total hip arthroplasty--does it really matter? A meta-analysis.
abstract: OBJECTIVE
  Discussion persists as to whether obesity negatively influences the outcome of hip arthroplasty. We performed a meta-analysis with the primary research question of whether obesity has a negative effect on short- and long-term outcome of total hip arthroplasty.
  
  
  METHODS
  We searched the literature and included studies comparing the outcome of hip arthroplasty in different weight groups. The methodology of the studies included was scored according to the Cochrane guidelines. We extracted and pooled the data. For continuous data, we calculated a weighted mean difference and for dichotomous variables we calculated a weighted odds ratio (OR). Heterogeneity was calculated using I(2) statistics.
  
  
  RESULTS
  15 studies were eligible for data extraction. In obese patients, dislocation of the hip (OR = 0.54, 95% CI: 0.38-0.75) (10 studies, n = 8,634), aseptic loosening (OR = 0.64, CI: 0.43-0.96) (6 studies, n = 5,137), infection (OR = 0.3, CI: 0.19-0.49) (10 studies, n = 7,500), and venous thromboembolism (OR = 0.56, CI: 0.32-0.98) (7 studies, n = 3,716) occurred more often. Concerning septic loosening and intraoperative fractures, no statistically significant differences were found, possibly due to low power. Subjective outcome measurements did not allow pooling because of high heterogeneity (I(2) = 68%).
  
  
  CONCLUSIONS
  Obesity appears to have a negative influence on the outcome of total hip replacement.
authors.affiliation: Department of Orthopaedic Surgery, Tergooi Ziekenhuizen, Hilversum, the Netherlands. Daniel@drhaverkamp.com
authors.forename: Daniël
authors.initials: D
authors.lastname: Haverkamp
authors.forename: Mark N
authors.initials: MN
authors.lastname: Klinkenbijl
authors.forename: Mathijs P
authors.initials: MP
authors.lastname: Somford
authors.forename: G H Rob
authors.initials: GH
authors.lastname: Albers
authors.forename: Harm M
authors.initials: HM
authors.lastname: van der Vis
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects; D006801:Humans; D007431:Intraoperative Complications / Q000209:etiology; D009765:Obesity / Q000150:complications*; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000209:etiology; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000209:etiology; D016896:Treatment Outcome