title: Autograft Versus Allograft in Anterior Cruciate Ligament Reconstruction: A Meta-analysis of Randomized Controlled Trials and Systematic Review of Overlapping Systematic Reviews.
abstract: OBJECTIVE
  To compare autograft with allograft in anterior cruciate ligament reconstruction by conducting a meta-analysis of randomized controlled trials (RCTs) and a systematic review of overlapping systematic reviews.
  
  
  METHODS
  PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched through June 28, 2014, to identify Level I and II evidence RCTs with a minimum follow-up of 2 years and systematic reviews that compared autograft with allograft in anterior cruciate ligament reconstruction. Both objective and subjective outcomes with respect to knee stability and function were meta-analyzed and summarized. The overall risk ratio (RR) or the weighted mean difference (WMD) was calculated using either a fixed- or random-effects model. The quality of evidence of the systematic review of overlapping systematic reviews was assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system.
  
  
  RESULTS
  Nine RCTs and 10 systematic reviews were included. In general, statistically significant differences in favor of autograft were observed for clinical failure (RR, 0.47; P = .0007), the Lachman test (RR, 1.18; P = .03), the instrumented laxity test (WMD, -0.88; P = .004), and the Tegner score (WMD, 0.36; P = .004). When subgroup analyses were conducted based on whether irradiation was used, autograft achieved better clinical outcomes than irradiated allograft in terms of the Lysholm score, clinical failure, the pivot-shift test, the Lachman test, the instrumented laxity test, and the Tegner score. In addition, there were no significant differences between the autograft and nonirradiated allograft groups for all 8 indices. The final results of this systematic review of overlapping systematic reviews were in accordance with our meta-analysis.
  
  
  CONCLUSIONS
  Autograft had greater advantages than irradiated allograft with respect to function and stability, whereas there were no significant differences between autograft and nonirradiated allograft.
  
  
  METHODS
  Level IV, meta-analysis of Level II, III, and IV studies.
authors.affiliation: Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zeng
authors.affiliation: Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Shu-guang
authors.initials: SG
authors.lastname: Gao
authors.affiliation: Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Tuo
authors.initials: T
authors.lastname: Yang
authors.affiliation: Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Luo
authors.affiliation: Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Yu-sheng
authors.initials: YS
authors.lastname: Li
authors.affiliation: Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China. Electronic address: lgh9640@sina.cn.
authors.forename: Guang-hua
authors.initials: GH
authors.lastname: Lei
mesh_terms: D064591:Allografts; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D064592:Autografts; D006801:Humans; D007719:Knee Joint / Q000601:surgery; D016017:Odds Ratio; D016032:Randomized Controlled Trials as Topic; D013710:Tendons / Q000637:transplantation*; D014182:Transplantation, Autologous; D014184:Transplantation, Homologous