The Developing Field of Scaffold-Free Tissue Engineering for Articular Cartilage Repair

Articular cartilage is critical for proper joint mobility as it provides a smooth and lubricated surface between articulating bones and allows for transmission of load to underlying bones. Extended wear or injury of this tissue can result in osteoarthritis, a degenerative disease affecting millions across the globe. Because of its low regenerative capacity, articular cartilage cannot heal on its own and effective treatments for injured joint restoration remain a challenge. Strategies in tissue engineering have been demonstrated as potential therapeutic approaches to regenerate and repair damaged articular cartilage. Although many of these strategies rely on the use of an exogenous three-dimensional scaffolds to regenerate cartilage, scaffold-free tissue engineering provides numerous advantages over scaffold-based methods. This review highlights the latest advancements in scaffold-free tissue engineering for cartilage and the potential for clinical translation. Although scaffolds are often incorporated into cartilage tissue engineering strategies as a three-dimensional architecture conducive to tissue formation, scaffold-free approaches are increasingly recognized for their ability to better recapitulate the native tissue formation process. Recent advancements in scaffold-free tissue engineering and success in clinical trials demonstrate the potential of these techniques to serve as viable therapies for repairing and restoring damaged cartilage.