title: Avoiding tunnel collisions between fibular collateral ligament and ACL posterolateral bundle reconstruction.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the risk of tunnel collisions of the fibular collateral ligament (FCL) and posterolateral bundle anterior cruciate ligament (PLB-ACL) tunnels during a combined FCL and double-dundle (DB) ACL reconstruction.
  
  
  METHODS
  Thirty-six 4th-generation synthetic femurs (Sawbones, Pacific Research Laboratories, Vashon, WA) were utilized, and two different femur sizes were used. A FCL tunnel and a PLB-ACL tunnel were reamed on each femur. The tunnels of synthetic specimens that did not have a collision were filled with an epoxy resin augmented with BaSO(4) and radiographic evaluation, and Multidetector CT exams of the specimens were performed.
  
  
  RESULTS
  The rate of tunnel collision when the FCL tunnel was reamed to a depth of 30 mm was 75 and 69.4% for the 25 mm depth. There was a significantly increased risk of tunnel collision when the FCL tunnel was reamed proximally with coronal angulations of 20° and 40°. No collisions were noted when the FCL tunnel was reamed parallel to the distal condylar line and with axial angulations of 20° and 40°.
  
  
  CONCLUSIONS
  This study provides new insight into tunnel positioning during a combined FCL and DB-ACL reconstruction. The results show that a concomitant FCL injury do not represent a contraindication to perform a DB-ACL reconstruction as long as the FCL tunnel is reamed with no proximal angulation and is directed anteriorly with an axial angulation between 20° and 40°.
authors.affiliation: Department of Orthopaedic Surgery, University of Palermo, Via del Vespro 159, 90100, Palermo, Italy. lawrencecamarda@unipa.it
authors.forename: Lawrence
authors.initials: L
authors.lastname: Camarda
authors.forename: Michele
authors.initials: M
authors.lastname: D'Arienzo
authors.forename: Giovanni Palermo
authors.initials: GP
authors.lastname: Patera
authors.forename: Leone
authors.initials: L
authors.lastname: Filosto
authors.forename: Robert F
authors.initials: RF
authors.lastname: LaPrade
mesh_terms: D016118:Anterior Cruciate Ligament / Q000601:surgery*; D001696:Biomechanical Phenomena; D017885:Collateral Ligaments / Q000601:surgery*; D003131:Combined Modality Therapy; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery*; D005360:Fibula / Q000601:surgery; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control*; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery; D008953:Models, Anatomic; D019651:Plastic Surgery Procedures / Q000009:adverse effects / Q000379:methods*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods