title: Effects of different initial bundle tensioning strategies on the outcome of double-bundle ACL reconstruction: a cohort study.
abstract: BACKGROUND
  This study was performed to investigate the effects of different strategies and initial tension applied to each one of the bundles, antero-medial (AM) and postero-lateral (PL), on clinical outcome in double bundle (DB) ACL reconstruction.
  
  
  METHODS
  One hundred fifty-one primary unilateral DB ACL reconstructions performed by a single surgeon from 1994 through 2002 were included in the study with a follow-up of at least 24 months. They were divided in the following 3 groups: Group I - Higher initial tension applied manually in the AM bundle compared to PL. II - Higher tension applied in the PL bundle compared to AM. III - The 2 bundles were attempted to be equally tensioned. All fixations were performed in 30 degrees of flexion. Group I = 59 patients, group II = 53 patients and group III = 39 patients. The groups had no statistical differences concerning demographic distribution. Clinical outcome was retrospectively evaluated by use of knee range of motion, manual knee laxity tests, KT-1000, Lysholm knee scale, subjective recovery scale and sports performance recovery scale. The differences of data were analyzed among the three groups.
  
  
  RESULTS
  Group I showed a significant extension deficit compared with groups II and III. ANOVA revealed a significant difference of anterior laxity measured by the KT-1000 (average KT difference of 2.1, 2.1 and 1.2 mm in Group I, II and III, respectively). A statistical difference was found among the three groups regarding subjective and sports performance recovery scales with Group II showing higher scores in recovery than Group I.
  
  
  CONCLUSIONS
  The current clinical study does not recommend manual maximum of initial tension applied to the anteromedial or posterolateral bundles with graft tension imbalance at 30 degrees of flexion in double-bundle ACL reconstruction to achieve a better clinical outcome.
authors.affiliation: Department of Orthopaedic Surgery, Tokyo Medical and Dental University Hospital, Tokyo, Japan. muneta.orj@tmd.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Muneta
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Koga
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Ju
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Yagishita
authors.forename: Ichiro
authors.initials: I
authors.lastname: Sekiya