My doctor recommended that I have surgery on my knee because of a problem with the cartilage. He said something about removing some cells and re-injecting them, but I don’t understand what he meant. Can you explain it?

For patients who have cartilage defects, there are a few ways to treat it. One procedure, called a autologous chondrocyte implantation involves two steps. First, the doctor will use a special needle to remove some cells from the cartilage in your knee. When the cells are removed, they are grown in a laboratory and regenerated. Once they are ready, the cells are reimplanted into your knee, which is the second procedure.