This is a case of a 25-year-old man from Italy who was in a car accident. He ended up with a large tear in the cartilage of his knee. A layer of bone underneath the cartilage was torn, too. Such an injury is now being treated with autologous chondrocyte implantation (ACI).
ACI is a two-step operation. First some cartilage cells (chondrocytes) are taken from the patient’s own knee (autologous). The harvest site is an area that doesn’t bear weight. The cells are taken to the lab to grow more cells. Four weeks later, a second surgery is done using the lab cells to patch the hole. Sounds simple, doesn’t it? But it’s not.
Here’s how it works. The lab-grown cells form a layer of tissue the same shape and size as the hole that must be plugged. A special two-sided membrane is used to make this happen. One side is smooth to keep anything from getting in. The other side allows chondrocytes in to reproduce. The chondrocyte side faces the bone and allows the implant to become part of the damaged bone.
The second step is called a matrix-induced autologous chondrocyte implantation (MACI). A special glue is used to fix the implant to the bone. The fibrin glue makes it possible for the doctor to use an arthroscope to do the operation. An arthroscope is a slender tool that’s inserted into the joint. There’s a tiny TV camera on the end so the doctor can see inside.
Without the special glue and new arthroscopic tools, this type of cartilage defect would require a big operation. The joint would have to be opened up. The implant would have to be sewn in place. There’s a good chance ligaments and tendons in the area would be damaged in the process of getting to the injured site.
The authors say fibrin glue and new surgical tools makes MACI using arthroscopic surgery a safe and simple way to repair deep cartilage tears. Things can only get better as other instruments are made for special types of operations like this one.