Challenges for cartilage regeneration

Abstract

Articular cartilage is a resilient connective tissue, which covers the surface of bones to facilitate their movements against each other. Due to unique mechanical properties, cartilage has a prominent role in locomotion and mobility of the human body. This tissue however has limited capability of regeneration and repair due to its low metabolism and avascular structure. Trauma, degenerative conditions and inflammatory arthritis lead to lifetime disability states and pain. The scope of this chapter is to first provide an overview of mechanical, biological and micro-architectural properties of articular cartilage and the effect of aging on these characteristics. Then the cartilage treatment techniques that have been proposed for different types of cartilage defects are discussed. Cell-based therapies, such as autologous chondrocyte implantation (ACI) technique, have been developed to achieve reproducible results regardless of patients’ age, gender and physical conditions. The second generation of ACI is a tissue engineering-based technique, which includes the use of appropriate cell type, bioactive molecules such as growth factors and proper scaffold to regenerate cartilage. The favourable types of cells, biological compounds and properties of biomaterials for cartilage regeneration have also been discussed in this chapter. Finally, the biomaterial products that have been examined in clinical trial for cartilage repair are outlined, and their properties and clinical results are discussed.