title: Single-bundle versus double-bundle reconstruction for anterior cruciate ligament rupture: a meta-analysis--does anatomy matter?
abstract: OBJECTIVE
  To determine whether double-bundle anterior cruciate ligament reconstruction leads to better restoration of anterior and rotational laxity and range of motion than single-bundle reconstruction.
  
  
  METHODS
  A search was performed in the Medline, Embase, CINAHL, and Cochrane databases. All randomized, quasi-randomized, and observational clinical trials that reported the outcome of double- versus single-bundle anterior cruciate ligament reconstruction were included in our meta-analysis. The primary outcomes were anterior laxity (KT arthrometer; MEDmetric, San Diego, CA), pivot shift, and range of motion. Subgroup analyses were performed for more than 2 years' follow-up, anatomic reconstruction, and nonanatomic reconstruction. The quality of the included studies was scored by use of the GRADE Checklist.
  
  
  RESULTS
  Included 12 studies in this meta-analysis, 5 of which were randomized. There was a statistically significant difference in favor of double-bundle reconstruction for anterior laxity (KT arthrometer difference, -0.6 mm), Lachman test (64% risk reduction of positive Lachman), and pivot-shift test (69% risk reduction of positive shift). Similar results were found for the subgroup with more than 2 years' follow-up and anatomic reconstructions. There were no significant differences for the subgroup with nonanatomic reconstructions, except a 2.6 times risk increase of extension deficit with nonanatomic double-bundle reconstruction compared with nonanatomic single-bundle reconstruction. Most of the included studies were found to have at least one serious limitation in study design.
  
  
  CONCLUSIONS
  In comparison with single-bundle reconstruction, double-bundle reconstruction showed less anterior laxity, as measured by the KT arthrometer and Lachman test, and better rotational laxity, as measured by the pivot-shift test. The majority of the included studies had at least one major limitation in study design that decreased the quality of the study.
  
  
  METHODS
  Level I, meta-analysis.
authors.affiliation: Department of Orthopedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Carola F
authors.initials: CF
authors.lastname: van Eck
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kopf
authors.forename: James J
authors.initials: JJ
authors.lastname: Irrgang
authors.forename: Leendert
authors.initials: L
authors.lastname: Blankevoort
authors.forename: Mohit
authors.initials: M
authors.lastname: Bhandari
authors.forename: Freddie H
authors.initials: FH
authors.lastname: Fu
authors.forename: Rudolf W
authors.initials: RW
authors.lastname: Poolman
mesh_terms: D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D006801:Humans; D007593:Joint Instability / Q000209:etiology / Q000517:prevention & control; D007718:Knee Injuries / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D007719:Knee Joint / Q000502:physiology / Q000601:surgery; D016059:Range of Motion, Articular; D016896:Treatment Outcome