title: The effect of cartilage and bone density of mushroom-shaped, photooxidized, osteochondral transplants: an experimental study on graft performance in sheep using transplants originating from different species.
abstract: BACKGROUND
  Differences in overall performance of osteochondral photooxidized grafts were studied in accordance of their species origin and a new, more rigorous cleansing procedure using alcohol during preparation.
  
  
  METHODS
  Photooxidized mushroom-shaped grafts of bovine, ovine, human and equine origin were implanted in the femoral condyles of 32 sheep (condyles: n = 64). No viable chondrocytes were present at the time of implantation. Grafts were evaluated at 6 months using plastic embedded sections of non-decalcified bone and cartilage specimens. Graft incorporation, the formation of cyst-like lesions at the base of the cartilage junction as well as cartilage morphology was studied qualitatively, semi-quantitatively using a score system and quantitatively by performing histomorphometrical measurements of percentage of bone and fibrous tissue of the original defects. For statistical analysis a factorial analysis of variance (ANOVA- test) was applied.
  
  
  RESULTS
  Differences of graft performance were found according to species origin and cleansing process during graft preparation. According to the score system cartilage surface integrity was best for equine grafts, as well as dislocation or mechanical stability. The equine grafts showed the highest percentage for bone and lowest for fibrous tissue, resp. cystic lesions. The new, more rigorous cleansing process decreased cartilage persistence and overall graft performance.
  
  
  CONCLUSIONS
  Performance of grafts from equine origin was better compared to bovine, ovine and human grafts. The exact reason for this difference was not proven in the current study, but could be related to differences in density of cartilage and subchondral bone between species.
authors.affiliation: Musculoskeletal Research Unit, Equine Hospital, Vetsuisse Faculty Zurich, University of Zurich, Switzerland. anja.waselau@gmx.net
authors.forename: Anja C
authors.initials: AC
authors.lastname: Waselau
authors.forename: Daniel
authors.initials: D
authors.lastname: Nadler
authors.forename: Jessika M V
authors.initials: JM
authors.lastname: Müller
authors.forename: Katalin
authors.initials: K
authors.lastname: Zlinszky
authors.forename: Monika
authors.initials: M
authors.lastname: Hilbe
authors.forename: Jörg A
authors.initials: JA
authors.lastname: Auer
authors.forename: Brigitte
authors.initials: B
authors.lastname: von Rechenberg
mesh_terms: D000818:Animals; D015519:Bone Density; D016025:Bone Transplantation; D001842:Bone and Bones / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects; D002356:Cartilage / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects / Q000637:transplantation*; D002417:Cattle; D005260:Female; D006736:Horses; D006801:Humans; D008027:Light; D010084:Oxidation-Reduction; D012756:Sheep; D014183:Transplantation, Heterologous