Biomechanical Properties of Silk-Derived 3D Bioprinted Scaffolds for Cartilage Regeneration: A Comprehensive Review

Cartilage regeneration remains a major clinical challenge because cartilage has limited healing capacity and must withstand substantial mechanical loading. Silk fibroin, a cocoon-derived biomaterial with tunable mechanical properties, has emerged as a promising scaffold material for cartilage tissue engineering. This systematic review evaluates the biomechanical performance, fabrication approaches, and regenerative potential of silk fibroin bioprinted scaffolds for cartilage repair. A systematic review was conducted according to PRISMA guidelines. Primary outcomes included scaffold mechanical properties relevant to cartilage function. Secondary outcomes included scaffold composition, fabrication methods, biological performance, clinical applications, and reported limitations. Of 918 identified records, 24 studies published between 2014 and 2025 met the inclusion criteria. Most were preclinical studies using silk fibroin-based hydrogels, often combined with hyaluronic acid, gelatin, collagen, or synthetic polymers. Mechanical properties varied according to scaffold composition and crosslinking methods. Reinforced scaffolds generally demonstrated improved stiffness, structural support, and load distribution. Silk fibroin scaffolds consistently supported chondrogenesis and cartilage-like tissue formation. However, challenges remain, including mechanical mismatch with native cartilage, construct instability, cell loss, and suboptimal degradation profiles. Overall, silk fibroin bioprinted scaffolds demonstrated support for chondrogenesis and cartilage-like tissue formation in preclinical studies for cartilage regeneration. Future research should focus on standardized biomechanical testing, long-term in vivo evaluation, and clinically relevant scaffold designs to facilitate translation toward functional cartilage repair.