Cartilage Regeneration Using a Fibrin and Autologous Cultured Chondrocytes Mixture in a Canine Model

Background: Various surgical methods have been designed to avoid the necessity of using periosteum, i.e. an operative weak point of autologous chondrocyte implantation (ACI) which is a representative method for treating articular cartilage injury. This study was performed in the attempt to develop a simple, injectable type of ACI to in order facilitate the surgical process. Methods: Seven of 10 dogs were used for the injectable type ACI using fibrin, while the remaining three dogs were used for implantation according to the previous surgical method using periosteum. The left knee of each dog was incised in order to expose the medial femoral condyle, and a circular defect was then made to 5mm in diameter on the articular cartilage of the exposed medial femoral condyle so that chondrocyte implantation using periosteum and the injectable chondrocyte implantation using fibrin glue could both be performed. At week 12 following surgery, the cartilage was observed and compared histologically with normal articular cartilage. Results: The surface of the cartilage newly generated at week 12 was very smooth and even, and it was also seen that the entire area was completely regenerated. Through the histological evaluation, IHC test, and electron microscope pictures, it was verified that collagen type II was normally expressed and that the ultrastructure of the regenerated tissue showed the normal cartilage properties. Conclusion: Gel-type ACI using fibrinfor articular cartilage defects of the knee, appears to be an effective method for the regeneration and growth of cartilage and also has many potential surgical advantages.