Effect of low-dose irradiation on structural and mechanical properties of hyaline cartilage-like fibrocartilage

Acta Orthop Traumatol Turc. 2013;47(2):127-33. doi: 10.3944/aott.2013.2709.

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.

Conclusion: Low-dose irradiation does not affect the mechanical properties of HCLF in vivo. However, structural changes such as chondrocyte clustering were observed.

MeSH terms

  • Animals
  • Biomechanical Phenomena
  • Cartilage, Articular / pathology*
  • Cartilage, Articular / radiation effects*
  • Cell Differentiation
  • Female
  • Fibrocartilage / physiology*
  • Knee Joint / cytology*
  • Rabbits
  • Radiation Dosage