REPAIR OF ARTICULAR CARTILAGE INJURY

Articular cartilage defects heal poorly and lead to consequences as osteoarthritis. Clinical experience has indicated that no existing medication would substantially promote the healing process, and the cartilage defect requires surgical replacement. Allograft decays quickly for multiple reasons including the preparation process and immune reaction, and the outcome is disappointing. The extreme shortage of sparing in articular cartilage has much discouraged the use of autograft, which requires modification. The concept that constructs a chondral or osteochondral construct for the replacement of injured native tissue introduces that of tissue engineering. Limited number of cells are expanded either in vitro or in vivo, and resided temporally on a scaffold of biomaterial, which also acts as a vehicle to transfer the cells to the recipient site. Three core elements constitute this technique: the cell, a biodegradable scaffold, and an environment suitable for cells to present their proposed activity. Modern researches have kept updating those elements for a better performance of such cultivation of living tissue.