title: Femoral footprint variation of the posterolateral bundle of the anterior cruciate ligament and double-bundle reconstruction.
abstract: BACKGROUND
  The study is aimed to observe the range of variation of the ACL PLB femoral footprint and investigate countermeasures for accurate femoral bone tunnel placement during double-bundle ACL reconstruction.
  
  
  METHODS
  The femoral insertions of the anteromedial bundle (AMB) and PLB of the ACL were dissected in 30 male cadaveric knees. The ACL footprint on the lateral intercondylar wall (LIW) was observed, and the shape of the LIW, the resident ridge, the angle between the ACL long axis and femoral axis (AA), and the vertical distance from the center of the PLB to the lowest cartilage border of the LIW (PD) were measured.
  
  
  RESULTS
  The area most populated by the ACL fibers was directly under the resident ridge. AA = 18.7°±15.25° with variation from -18° to 56°, and PD=7.02±1.47 mm with variation from 3.75 to 11.08 mm. Both discrete values were very large in both groups of data. There were two kinds of LIW: trapezoidal (8 knees) and triangular (21 knees). Both AA and PD values exhibited significant differences between the two types of LIWs (P=0.00).
  
  
  CONCLUSIONS
  AA and PD vary among individuals. The insertions and centers of the PLB cannot be exactly anatomically determined with one size. For double-bundle ACL reconstruction, an individualized intraoperative footprint observation for fresh cases with footprint remnants, or resident ridge and anteromedial bundle-interval identification for old ACL tears, can be reasonable methods for posterolateral tunnel orientation.
  
  
  CONCLUSIONS
  Clinical relevance is observe the range of variation of the PLB femoral footprint for clinical double-bundle ACL reconstruction.
authors.affiliation: Department of Sports Medical, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People Hospital), Shenzhen 518000, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Lu
authors.affiliation: Department of Sports Medical, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People Hospital), Shenzhen 518000, PR China.
authors.forename: Weimin
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Department of Sports Medical, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People Hospital), Shenzhen 518000, PR China.
authors.forename: Liangquan
authors.initials: L
authors.lastname: Peng
authors.affiliation: Department of Sports Medical, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People Hospital), Shenzhen 518000, PR China.
authors.forename: Wenzhe
authors.initials: W
authors.lastname: Fen
authors.affiliation: Department of Sports Medical, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People Hospital), Shenzhen 518000, PR China.
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Sports Medical, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People Hospital), Shenzhen 518000, PR China.
authors.forename: Yangkan
authors.initials: Y
authors.lastname: Ou
authors.affiliation: Department of Sports Medical, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People Hospital), Shenzhen 518000, PR China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Sports Medical, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People Hospital), Shenzhen 518000, PR China. Electronic address: szhzwm@126.com.
authors.forename: Daping
authors.initials: D
authors.lastname: Wang
authors.affiliation: Biomechanics and Medical Information Institute, Beijing University of Technology, Beijing 100022, PR China. Electronic address: yjzeng@bjut.edu.cn.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Zeng
mesh_terms: D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods; D002102:Cadaver; D005269:Femur / Q000033:anatomy & histology*; D006801:Humans; D007719:Knee Joint / Q000033:anatomy & histology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: Anatomic reconstruction; Anterior cruciate ligament; Posterolateral bundle; Resident ridge; Variation