Cartilage implantation or transplantation is a possible remedy for persons with severe knee pain and loss of mobility. Damaged cartilage is its main cause in aging persons, athletes and those with diseases like rheumatoid arthritis. The poor healing capacity of damaged cartilage makes treatment difficult. Articular cartilage in the knees is made up of chondrocytes i.e. cartilage cells that are supported by a highly specialised tissue composed of 80% water, collagen and proteoglycans. This tissue makes articular cartilage extremely smooth, elastic and capable of withstanding up to 65 times the body weight. However, when things go wrong, cartilage has little capacity to heal itself, as it lacks blood supply and lymphatic drainage, and mainly derives nutrition from the synovial fluid in the knee. Autologous Chondrocyte Implantation (ACI), also known as Autologous Chondrocyte Transplantation (ACT) is a globally accepted remedy of knee pain and loss of mobility.

Autologous chondrocyte transplantation (i.e. Cartilage implantation or transplantation of cartilage cells from the patient’s own body after culturing) starts with a small biopsy is taken from a non-load-bearing part of the knee through arthroscopic surgery. This piece of live articular cartilage (roughly the size of a pea) is transported to the laboratory in a special culture medium. There, under a strictly controlled environment, chondrocyte cells are isolated from the tissue, and multiplied with cell-culture techniques. After the numbers of such cells has grown to approximately 12 million cartilage cells in 0.4ml of medium, surgery is performed on the knee, and the cultured chondrocytes are injected to the site of the damage, where it will grow. This procedure is known as Autologous Cartilage Implantation or Transplantation (ACI or ACT).