title: Regional fibrocartilage variations in human anterior cruciate ligament tibial insertion: a histological three-dimensional reconstruction.
abstract: OBJECTIVE
  We studied anterior cruciate ligament (ACL) tibial insertion architecture in humans and investigated regional differences that could suggest unequal force transmission from ligament to bone.
  
  
  METHODS
  ACL tibial insertions were processed histologically. With Photoshop software, digital images taken from the histological slides were collaged, contour lines were drawn, and different gray values were filled based on the structure. The data were exported to Amira software for three-dimensional reconstruction.
  
  
  RESULTS
  The uncalcified fibrocartilage (UF) layer was divided into three regions: lateral, medial and posterior according to the architecture. The UF zone was significantly thicker laterally than medially or posteriorly (p < 0.05). Similarly, the calcified fibrocartilage (CF) thickness was significantly greater in the lateral part of the enthesis compared to the medial and posterior parts (p < 0.05).
  
  
  CONCLUSIONS
  The UF quantity (more UF laterally) corresponding to the CF quantity (more CF laterally) at the ACL tibial insertion provides further evidence suggesting that the load transferred from the ACL to the tibia was greater laterally than medially and posteriorly.
authors.affiliation: Center for Joint Surgery, Southwest Hospital, Third Military Medical University , Chongqing , P.R. China .
authors.forename: Can
authors.initials: C
authors.lastname: Dai
authors.forename: Lin
authors.initials: L
authors.lastname: Guo
authors.forename: Liu
authors.initials: L
authors.lastname: Yang
authors.forename: Yi
authors.initials: Y
authors.lastname: Wu
authors.forename: Jingyue
authors.initials: J
authors.lastname: Gou
authors.forename: Bangchun
authors.initials: B
authors.lastname: Li
mesh_terms: D000328:Adult; D016118:Anterior Cruciate Ligament / Q000033:anatomy & histology*; D002113:Calcification, Physiologic; D005260:Female; D051445:Fibrocartilage / Q000033:anatomy & histology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008022:Ligaments / Q000473:pathology; D008297:Male; D008875:Middle Aged; D013977:Tibia / Q000033:anatomy & histology*; D055815:Young Adult
keywords: ACL; enthesis; fibrocartilage; force transmission; thickness