title: Transportal femoral drilling creates more horizontal ACL graft orientation compared to transtibial drilling: A 3D CT imaging study.
abstract: BACKGROUND
  The principle of anatomic anterior cruciate ligament (ACL) reconstruction is to create a femoral and tibial tunnel that resembles the insertion of the native ACL. Anatomic reconstruction leads to a more horizontal graft orientation that provides more rotational stability. The aim of this study is to investigate the best method to achieve anatomical reconstruction of femoral insertion of the ACL and thus, a more horizontal orientation of the ACL. We compared tunnel position and orientation between transportal femoral drilling technique and transtibial technique.
  
  
  METHODS
  Thirty-two patients were included. Post-operative CT scans were obtained and femur, tibia and ACL tunnels were reconstructed. The position and orientation of tibial and femoral tunnels were quantified using the quadrant method, and femoral tunnel length, ellipticity and posterior wall breakage were assessed. We also investigated clinical outcome.
  
  
  RESULTS
  Analyses show that transportal drilled femoral tunnels were situated significantly lower than transtibial drilled tunnels (p<0.0001), resulting in a significantly more horizontal oriented ACL in the transportal group in coronal (p<0.0001) and sagittal plane (p=0.01). No differences were observed in depth of femoral tunnel position (p=0.44). Femoral tunnel length was shorter in the transportal group (p=0.01) with a more ellipsoidal femoral aperture (p=0.01). There were no differences between both groups in tibial position. There were no differences in clinical outcome measure between the transportal and transtibial groups.
  
  
  CONCLUSIONS
  This study indicates that transportal drilling of the femoral tunnel leads to a more horizontal graft orientation of the ACL, without differences in clinical outcome.
authors.affiliation: Monica Orthopedic Research (MoRe) Foundation, Monica Hospital, Antwerp, Belgium. Electronic address: stefanclockaerts@hotmail.com.
authors.forename: S
authors.initials: S
authors.lastname: Clockaerts
authors.affiliation: Monica Orthopedic Research (MoRe) Foundation, Monica Hospital, Antwerp, Belgium.
authors.forename: A
authors.initials: A
authors.lastname: Van Haver
authors.affiliation: Monica Orthopedic Research (MoRe) Foundation, Monica Hospital, Antwerp, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Verhaegen
authors.affiliation: Monica Orthopedic Research (MoRe) Foundation, Monica Hospital, Antwerp, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Vuylsteke
authors.affiliation: Monica Orthopedic Research (MoRe) Foundation, Monica Hospital, Antwerp, Belgium.
authors.forename: T
authors.initials: T
authors.lastname: Leenders
authors.affiliation: Monica Orthopedic Research (MoRe) Foundation, Monica Hospital, Antwerp, Belgium.
authors.forename: K C
authors.initials: KC
authors.lastname: Lagae
authors.affiliation: Monica Orthopedic Research (MoRe) Foundation, Monica Hospital, Antwerp, Belgium; Faculty of Medicine, Ghent University, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Verdonk
mesh_terms: D000328:Adult; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D064592:Autografts / Q000601:surgery; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D000072458:Orientation, Spatial; D012399:Rotation; D013977:Tibia / Q000000981:diagnostic imaging* / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D014182:Transplantation, Autologous / Q000379:methods; D055815:Young Adult
keywords: 3D CT; Anterior cruciate ligament; Reconstruction; Transportal; Transtibial