title: The influence of nonanatomical insertion and incongruence of meniscal transplants on the articular cartilage in an ovine model.
abstract: BACKGROUND
  Adequate size matching and anatomically correct positioning must be recognized as essential factors influencing the outcome of meniscal transplantation.
  
  
  OBJECTIVE
  Nonanatomical insertion and incongruence of meniscal transplants has an influence on the development of degenerative changes.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Ten female sheep were used for this animal study. Both knees (N = 20) were divided into 3 groups, subjected to either meniscectomy (group I; n = 10), to a medial meniscal autograft transplantation with a nonanatomical insertion of the anterior and posterior horn (group II; n = 5), or a meniscal autograft transplantation from the opposite knee as an incongruent meniscal autograft (group III; n = 5). After 6 months, radiographic (Fairbank's criteria), macroscopic (Jackson score), and histological evaluation by light microscopy (Mankin score) and scanning electron microscopy of the articular cartilage was performed.
  
  
  RESULTS
  All applied evaluation methods demonstrated that nonanatomical insertion of meniscal transplants resulted in the highest amount of degenerative cartilage changes. The histological assessment even revealed a significantly enlarged cartilage damage for the non-anatomic-positioned meniscal transplants in relation to the meniscectomized knees. Furthermore, the incongruent meniscal transplants demonstrated a significantly better cartilage situation than nonanatomically inserted meniscal transplants.
  
  
  CONCLUSIONS
  The histological evaluation demonstrated clearly that a nonanatomically inserted meniscal transplant leads to degenerative cartilage changes that are worse than that after meniscectomy.
  
  
  CONCLUSIONS
  Precise anatomic positioning is mandatory for the potential chondroprotective effect of meniscal transplants.
authors.affiliation: Orthopaedic Department, Hannover Medical School, Anna-von-Borries-Str. 1-7, D-30625 Hannover, Germany. gabriela.von.lewinski@annastift.de
authors.forename: Gabriela
authors.initials: G
authors.lastname: von Lewinski
authors.forename: Dieter
authors.initials: D
authors.lastname: Kohn
authors.forename: Carl Joachim
authors.initials: CJ
authors.lastname: Wirth
authors.forename: Djordje
authors.initials: D
authors.lastname: Lazovic
mesh_terms: D000818:Animals; D002357:Cartilage Diseases / Q000473:pathology; D002358:Cartilage, Articular / Q000033:anatomy & histology* / Q000473:pathology; D005260:Female; D008592:Menisci, Tibial / Q000503:physiopathology / Q000601:surgery / Q000637:transplantation*; D023421:Models, Animal; D012756:Sheep