Hydrogels in cartilage tissue engineering, in: Applications of hydrogels in regenerative medicine. Gels Handbook: Fundamentals, Properties, Applications

Due to the absence of blood and lymphatic circulation, damages of cartilage do not spontaneously repair, and the associated pain is one of the most frequent causes of invalidity, mainly in elderly people. This chapter examines composition, morphology and functions of articular cartilage, providing basic information of its most frequent injuries and pathologies. Surgical treatments are reported and the regenerative medicine approaches trough the use of proper materials and cells are in-depth discussed. The requirements for the scaffold materials are also considered in terms of architecture, mechanical properties and molecular recognition capabilities, together with methods of fabrication and/or modification. In particular, the use of hydrogels (HGs) is reviewed, both from synthetic and natural polymers, as elective materials for cartilage repair. Their mechanical properties, degradation profile as well as production and distribution of ECM can be tailored by the polymer chemistry, gelation mechanism and design parameters. HGs can offer alternative solutions to traditional “open site” surgical approaches with minimally invasive applications exploiting “in situ” gelation methods or smart sol-gel transitions.