Chondrocyte transplantation and experimental treatment options for articular cartilage defects

Current treatment options for injured articular cartilage have resulted in temporary improvements in clinical symptoms and functional levels. None of these modalities, however, has resulted in restoration of an articular surface that is able to withstand long-term joint loading and function. As a result, numerous investigators have attempted to devise alternative therapies. The limited regnerative potential of articular cartilage has led investigators to attempt using cells with the potential for differentiation and proliferation to repair chondral defects. Chondrocyte transplantation, both allogeneic and autogenous, has shown early promising results in regenrating hyaline-like tissue in both animals and humans. Encouraging results in animals have also been demonstrated with alternative sources of osteoprogenitor cells as grafts, as well as with natural/synthetic implants and the use of growth factors and cytokines. However, despite encouraging short-term results, long-term data concerning the regenerate tissue are still needed. As more research is being conducted to understand the processes of cartilage maintenance and healing, there is hope that cartilage regeneration and neochondrogenesis will be possible in the future.