The Biologic Approach for Managing Cartilage Injury: Where are We Now™

Articular cartilage or Hyaline cartilage consists of 95% type 2 collagen, water, proteoglycans and chondrocytes. Cartilage functions to decrease friction, distribute loads, resists shear/compression, and also as a shock-absorbing cushion. It has the characteristics of alymphatic, avascular, aneural, anisotropic, biphasic and viscoelastic. Cartilage can be damaged by direct trauma, loss of underlying bone structure, a genetic defect in the normal structure and chemical/enzymatic threats. Articular cartilage injuries are commonly caused by sports and recreational activities. Articular cartilage damage has inherent limited healing potential; hence it remains a challenging problem for orthopedic surgeons. There are three eras of cartilage repair technique: the pre-Autologous Chondrocyte Transplantation Era or Autologous Chondrocytes Implantation (ACI), Matrix – Assisted Chondrocytes Implantation (MACI) era and Regenerative Medicine era. In 1743 Hunter stated, “Cartilage injury is a troublesome thing and once injured is seldom repaired“. Nowadays, there are a lot of modalities for cartilage repair such as microfracture, mosaicplasty, ACI, MACI, platelet-rich plasma, bone marrow aspirate concentrate, orthokine or interleukin receptor antagonist and Matrix metalloproteinases (MMPs) inhibitor.