title: Relation between osteonecrosis of the femoral head and PAI-1 4G/5G gene polymorphism: a meta-analysis.
abstract: OBJECTIVE
  The aim of this study was to investigate the association of plasminogen activator inhibitor-1 (PAI-1) 4G/5G gene polymorphism and osteonecrosis of the femoral head (ONFH).
  
  
  METHODS
  The pooled relative risk ratio (RR) and 95% confidence intervals (95% CI) were calculated using the the RevMan 5.0 software.
  
  
  RESULTS
  The present study included 969 patients with ONFH and 419 healthy controls. The Meta analysis results showed: There is association between PAI-1 gene 4G/5G polymorphism and the increasing risk of ONFH (allele model: RR = 1.24, 95% CI = 1.16 ~ 1.33; dominant genetic model: RR = 1.12, 95% CI = 1.05 ~ 1.18). It was found that the association between PAI-1 gene 4 G/5 G polymorphism and the susceptibility of ONFH (P < 0.05) through the comparison of Caucasian population and Asian people according to the analysis of different races.
  
  
  CONCLUSIONS
  There is association between PAI-1 gene 4 G/5 G polymorphism and the increasing of the susceptibility of ONFH.
authors.affiliation: Department of Orthopaedic Surgery, Beijing Tian Tan Hospital, Capital Medical University 100050, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: Department of Orthopaedic Surgery, Beijing Tian Tan Hospital, Capital Medical University 100050, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Orthopaedic Surgery, Beijing Tian Tan Hospital, Capital Medical University 100050, China.
authors.forename: Haitao
authors.initials: H
authors.lastname: Pan
keywords: Plasminogen activator inhibitor-1; meta-analysis; osteonecrosis of the femoral head