title: Effect of low-dose irradiation on structural and mechanical properties of hyaline cartilage-like fibrocartilage.
abstract: OBJECTIVE
  The aim of this study was to analyze the effect of low-dose irradiation on fibrous cartilage and to obtain a hyaline cartilage-like fibrocartilage (HCLF) with similar structural and mechanical properties to hyaline cartilage.
  
  
  METHODS
  An osteochondral defect was created in 40 knees of 20 rabbits. At the 7th postoperative day, a single knee of each rabbit was irradiated with a total dose of 5.0 Gy in 1.0 Gy fractions for 5 days (radiotherapy group), while the other knee was not irradiated (control group). Rabbits were then divided into four groups of 5 rabbits each. The first three groups were sacrificed at the 4th, 8th and the 12th postoperative weeks and cartilage defects were macroscopically and microscopically evaluated. The remaining group of 5 rabbits was sacrificed at the 12th week and biomechanical compression tests were performed on the cartilage defects.
  
  
  RESULTS
  There was no significant biomechanical difference between the radiotherapy and the control group (p=0.686). There was no significant macroscopic and microscopic difference between groups (p=0.300). Chondrocyte clustering was observed in the irradiated group.
  
  
  CONCLUSIONS
  Low-dose irradiation does not affect the mechanical properties of HCLF in vivo. However, structural changes such as chondrocyte clustering were observed.
authors.affiliation: Department of Orthopedics and Traumatology, Anadolu Hospital, Bursa, Turkey.
authors.forename: Tevfik
authors.initials: T
authors.lastname: Öncan
authors.forename: Burak
authors.initials: B
authors.lastname: Demirağ
authors.forename: Cenk
authors.initials: C
authors.lastname: Ermutlu
authors.forename: Ulviye
authors.initials: U
authors.lastname: Yalçinkaya
authors.forename: Lütfü
authors.initials: L
authors.lastname: Özkan
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002358:Cartilage, Articular / Q000473:pathology* / Q000528:radiation effects*; D002454:Cell Differentiation; D005260:Female; D051445:Fibrocartilage / Q000502:physiology*; D007719:Knee Joint / Q000166:cytology*; D011817:Rabbits; D011829:Radiation Dosage