title: Biomechanical analysis of an anatomic anterior cruciate ligament reconstruction.
abstract: BACKGROUND
  The focus of most anterior cruciate ligament reconstructions has been on replacing the anteromedial bundle and not the posterolateral bundle.
  
  
  OBJECTIVE
  Anatomic two-bundle reconstruction restores knee kinematics more closely to normal than does single-bundle reconstruction.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Ten cadaveric knees were subjected to external loading conditions: 1) a 134-N anterior tibial load and 2) a combined rotatory load of 5-N x m internal tibial torque and 10-N x m valgus torque. Resulting knee kinematics and in situ force in the anterior cruciate ligament or replacement graft were determined by using a robotic/universal force-moment sensor testing system for 1) intact, 2) anterior cruciate ligament deficient, 3) single-bundle reconstructed, and 4) anatomically reconstructed knees.
  
  
  RESULTS
  Anterior tibial translation for the anatomic reconstruction was significantly closer to that of the intact knee than was the single-bundle reconstruction. The in situ force normalized to the intact anterior cruciate ligament for the anatomic reconstruction was 97% +/- 9%, whereas the single-bundle reconstruction was only 89% +/- 13%. With a combined rotatory load, the normalized in situ force for the single-bundle and anatomic reconstructions at 30 degrees of flexion was 66% +/- 40%and 91% +/- 35%, respectively.
  
  
  CONCLUSIONS
  Anatomic reconstruction may produce a better biomechanical outcome, especially during rotatory loads.
  
  
  CONCLUSIONS
  Results may lead to the use of a two-bundle technique.
authors.affiliation: Musculoskeletal Research Center, Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Yagi
authors.forename: Eric K
authors.initials: EK
authors.lastname: Wong
authors.forename: Akihiro
authors.initials: A
authors.lastname: Kanamori
authors.forename: Richard E
authors.initials: RE
authors.lastname: Debski
authors.forename: Freddie H
authors.initials: FH
authors.lastname: Fu
authors.forename: Savio L-Y
authors.initials: SL
authors.lastname: Woo
mesh_terms: D000704:Analysis of Variance; D016118:Anterior Cruciate Ligament / Q000033:anatomy & histology / Q000601:surgery*; D001696:Biomechanical Phenomena; D002102:Cadaver; D006801:Humans