Challenges and Strategies in Hydrogel-Based Cartilage Regeneration

The increase in older adults and active lifestyles has made chondral and osteochondral lesions common in the population, making them one of the central challenges in orthopedics. Although hydrogel-based regenerative medicine offers an encouraging therapeutic option for these lesions, important obstacles still prevent these therapies from reaching the clinic. In view of these factors, we adopted a risk-based approach for this review, in line with the current legislative requirements in clinical translation and clinical trials. We identified the factors that could undermine patient safety or lead to poor outcomes. Then, we outlined solutions to remedy these problems that integrate hydrogel technology, clinical/pharmaceutical/surgical protocols, and post-operative follow-up. Upcoming studies should give priority to the development of hydrogel scaffolds modified to mimic cartilage's mechanical and physicochemical properties, together with patient-specific features. Other crucial characteristics are host-tissue integration, long-lasting cartilage tissue regeneration, and a positive outcome. In parallel, to scale complex and costly innovations, efforts should focus on a harmonized, simplified legislative landscape, optimized standards, and established follow-up protocols. Getting through this "valley of death" between research and innovation is strategic for reaching the clinics and the largest number of patients.