Application of Hydrogels in Cartilage Tissue Engineering

Background: Cartilage has limited ability for self-repairing, prompting the search for cartilage substitutes that can repair cartilage defects. Hydrogels have attracted attention as cartilage substitutes, since their mechanical properties, swelling ability and lubricating behavior are similar to extracellular matrix of articular cartilage. Hydrogels can be of natural, synthetic or hybrid origin, and hydrogels can encapsulate stem cells and/or be loaded with growth factors to promote cell differentiation into a chondrogenic phenotype. Objective and Results: This review summarizes basic research advances in using hydrogels to repair cartilage defects. The raw materials, stem cells and growth factors used to prepare hydrogels are discussed. Conclusion: Substantial success has been achieved in small animal models of cartilage repair and regeneration, but further research is needed to improve hydrogels' mechanical properties and their integration with surrounding tissues.