title: Anatomical and nonanatomical double-bundle anterior cruciate ligament reconstruction: importance of femoral tunnel location on knee kinematics.
abstract: BACKGROUND
  Studies have suggested that double-bundle anterior cruciate ligament reconstruction may restore intact knee kinematics better than single-bundle anterior cruciate ligament reconstruction. Although the tunnel position of the femoral anteromedial bundle is well established, the effects of different posterolateral bundle positions on knee kinematics are unknown.
  
  
  OBJECTIVE
  Double-bundle anterior cruciate ligament reconstruction with an anatomical (shallow) femoral posterolateral bundle tunnel placement will restore knee kinematics more closely than will a nonanatomical (deep) femoral posterolateral bundle tunnel position.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  In 12 human cadaveric knees, the kinematics of the intact knee, anterior cruciate ligament-deficient knee, and double-bundle anterior cruciate ligament-reconstructed knees with nonanatomical femoral posterolateral tunnel placement and anatomical posterolateral bundle placement were determined in response to a 134-N anterior tibial load and a combined rotatory load of 10 N x m valgus and 4 N x m internal tibial rotation using a robotic/universal force moment sensor testing system. Statistical analyses were performed using a 2-way analysis of variance test.
  
  
  RESULTS
  Double-bundle anterior cruciate ligament reconstruction with nonanatomical posterolateral bundle placement showed significantly higher anterior tibial translation under anterior tibial and combined rotatory load than did the intact knee at 0 degrees and 30 degrees of knee flexion (P < .05). Reconstruction with an anatomical posterolateral tunnel placement restored the intact knee kinematics and showed significantly lower anterior tibial translation under anterior tibial and combined rotatory load when compared with reconstruction with nonanatomical posterolateral placement (P < .05).
  
  
  CONCLUSIONS
  Double-bundle anterior cruciate ligament reconstruction using the anatomical posterolateral bundle tunnel position restores the intact knee kinematics. A nonanatomical posterolateral bundle position results in rotatory instability.
  
  
  CONCLUSIONS
  Double-bundle anterior cruciate ligament reconstruction should be performed using anatomical tunnel placement of the anteromedial and posterolateral bundles. Nonanatomical double-bundle reconstruction may fail to show any clinical superiority to single-bundle reconstruction and should be avoided.
authors.affiliation: Department of Trauma, Hand, and Reconstructive Surgery, Wilhelms University Muenster, Waldeyer Strasse 1, 48149 Muenster, Germany. thore.zantop@ukmuenster.de
authors.forename: Thore
authors.initials: T
authors.lastname: Zantop
authors.forename: Nadine
authors.initials: N
authors.lastname: Diermann
authors.forename: Tobias
authors.initials: T
authors.lastname: Schumacher
authors.forename: Steffen
authors.initials: S
authors.lastname: Schanz
authors.forename: Freddie H
authors.initials: FH
authors.lastname: Fu
authors.forename: Wolf
authors.initials: W
authors.lastname: Petersen
mesh_terms: D000368:Aged; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D001696:Biomechanical Phenomena; D002102:Cadaver; D005269:Femur / Q000033:anatomy & histology* / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D008875:Middle Aged; D013709:Tendon Transfer / Q000379:methods*; D014481:United States