title: Anatomic and nonanatomic double-bundle anterior cruciate ligament reconstruction: an in vivo kinematic analysis.
abstract: BACKGROUND
  There have been no direct in vivo biomechanical comparisons performed between an anatomic double-bundle (ADB) and a nonanatomic double-bundle (NADB) anterior cruciate ligament (ACL) reconstruction.
  
  
  OBJECTIVE
  There are differences in kinematic outcomes between ADB and NADB ACL reconstruction techniques.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Twenty-six consecutive patients (mean age, 30 years; range, 18-32 years; 23 men, 3 women; 17 right knees, 9 left knees) with an isolated ACL injury were included in the study. The first 13 consecutive patients underwent NADB reconstruction (combination of a single-bundle and an over-the-top reconstruction), and the following 13 consecutive patients were treated with an ADB approach (using 2 tibial tunnels and 2 femoral tunnels placed in the center of the native femoral and tibial insertion sites). Grafts were pretensioned at 80 N and secured with cortical fixation systems under manual maximum force tension. Standard clinical laxity and pivot-shift tests were quantified at time zero before and after ACL reconstruction by means of a surgical navigation system dedicated to kinematic assessment; displacement of the medial and lateral compartments during the tests was also analyzed.
  
  
  RESULTS
  The ADB-reconstructed knees showed a larger preoperative-to-postoperative difference in anterior-posterior tibial plateau displacement of the medial and lateral compartments when compared with the NADB-reconstructed knees during the internal-external rotation test at 30° of flexion (P < .050). No other significant differences in laxity or pivot-shift values were noted. The mean surgical time for ADB reconstruction was significantly higher than that for NABD reconstruction (62 ± 13 and 43 ± 10 minutes, respectively; P < .0001).
  
  
  CONCLUSIONS
  Results showed a greater anterior-posterior translation of both compartments during the rotational passive laxity test in the ADB reconstruction group or overconstraint caused by the NADB technique. The 2 analyzed double-bundle ACL reconstructions did not show any significant quantitative difference in isolated anterior-posterior laxity and pivot-shift phenomenon at time zero.
  
  
  CONCLUSIONS
  Nonanatomic double-bundle ACL reconstruction can control anterior-posterior laxity and the pivot-shift phenomenon as well as ABD ACL reconstruction.
authors: Giulio Maria Marcheggiani Muccioli, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, via di Barbiano, 1/10, Bologna, Italy 40136. marcheggianimuccioli@me.com.
authors: Stefano
authors: S
authors: Zaffagnini
authors: Giulio Maria
authors: GM
authors: Marcheggiani Muccioli
authors: Cecilia
authors: C
authors: Signorelli
authors: Nicola
authors: N
authors: Lopomo
authors: Alberto
authors: A
authors: Grassi
authors: Tommaso
authors: T
authors: Bonanzinga
authors: Marco
authors: M
authors: Nitri
authors: Maurilio
authors: M
authors: Marcacci
mesh_terms: D000293:Adolescent; D000328:Adult; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D001696:Biomechanical Phenomena / Q000502:physiology; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology / Q000601:surgery*; D007719:Knee Joint / Q000503:physiopathology* / Q000601:surgery*; D008297:Male; D061646:Operative Time; D009984:Orthopedic Fixation Devices; D012399:Rotation; D025321:Surgery, Computer-Assisted; D013709:Tendon Transfer; D013710:Tendons / Q000637:transplantation; D055815:Young Adult
keywords: anatomic double-bundle reconstruction; anterior cruciate ligament; computer-assisted surgery; laxity; nonanatomic double-bundle reconstruction; pivot shift