title: The shape and the thickness of the anterior cruciate ligament along its length in relation to the posterior cruciate ligament: a cadaveric study.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the shape of the native anterior cruciate ligament (ACL) along its length in relation to the posterior cruciate ligament (PCL) and compare it with the size of the 3 commonly used autografts (bone-patellar tendon-bone [BPTB], single-bundle hamstring, and double-bundle hamstring).
  
  
  METHODS
  With the knee in extension, we filled the intercondylar notch with paraffin, fixing the cruciate ligaments in their natural position, in 8 cadaveric specimens. The ACL-PCL tissue specimen, embedded in paraffin, was removed en bloc. Gross sections were prepared in the coronal plane and were evaluated histologically. The width, thickness, and cross-sectional area of both the ACL and PCL were determined. The dimensions of the semitendinosus tendon (ST), gracilis tendon (GT), and BPTB grafts were measured and compared with those of the native ACL.
  
  
  RESULTS
  The PCL occupies the largest part of the intercondylar area, leaving only a small space for the ACL in knee extension. The ACL midsubstance has a width of 5 mm, resembling a band shape. Only before its tibial insertion does the ACL fan out and take the form of its tibial attachment. The BPTB graft has a thickness of 5.8 mm, whereas the ST and GT grafts have a thickness of 6.25 mm and 4.5 mm, respectively, and are comparable to the midsubstance of the ACL but undersized in the tibial insertion (P = .0016 for BPTB graft, P = .002 for ST graft, and P = .0003 for GT graft). A quadruple-looped ST-GT graft, with a diameter of 8 mm, is oversized in the midsubstance (P = .0002) but fits better in the tibial attachment.
  
  
  CONCLUSIONS
  The ACL midsubstance has a width of 5 mm, resembling a band shape. Before its tibial insertion, the ACL fans out like a trumpet, taking the form of its wide tibial attachment.
  
  
  CONCLUSIONS
  The dimensions of the native ACL have to be considered in graft selection for anatomic ACL reconstruction.
authors.affiliation: Orthopaedic Sports Medicine Center of Ioannina, Department of Orthopaedic Surgery, University of Ioannina, Ioannina, Greece.
authors.forename: Eleni
authors.initials: E
authors.lastname: Triantafyllidi
authors.forename: Nikolaos K
authors.initials: NK
authors.lastname: Paschos
authors.forename: Anna
authors.initials: A
authors.lastname: Goussia
authors.forename: Nektaria-Marianthi
authors.initials: NM
authors.lastname: Barkoula
authors.forename: Dimitrios A
authors.initials: DA
authors.lastname: Exarchos
authors.forename: Theodore E
authors.initials: TE
authors.lastname: Matikas
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Malamou-Mitsi
authors.forename: Anastasios D
authors.initials: AD
authors.lastname: Georgoulis
mesh_terms: D000368:Aged; D016118:Anterior Cruciate Ligament / Q000033:anatomy & histology*; D059549:Anterior Cruciate Ligament Reconstruction; D064594:Bone-Patellar Tendon-Bone Grafts / Q000033:anatomy & histology*; D002102:Cadaver; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000033:anatomy & histology; D008297:Male; D008875:Middle Aged; D017847:Patellar Ligament / Q000033:anatomy & histology; D016119:Posterior Cruciate Ligament / Q000033:anatomy & histology*; D012016:Reference Values