What is the Articular Cartilage?
Articular or hyaline cartilage is the tissue that covers bone surface of the knee which helps in smooth interaction between the two bones in the knee joint. It has less capacity to repair by itself because there is no direct blood supply to cartilage.
What is Cartilage Replacement?
Cartilage replacement is a surgical procedure performed to replace the worn-out cartilage with new cartilage.
Indications for Cartilage Replacement
It is usually performed to treat small areas of cartilage damage usually caused by sports or traumatic injuries. It is not indicated if you have advanced arthritis of the knee.
Cartilage Replacement Procedure
Cartilage replacement helps relieve pain, restore normal function, and can delay or prevent the onset of arthritis. The goal of the cartilage replacement procedures is to stimulate the growth of new hyaline cartilage. Various arthroscopic procedures involved in cartilage replacement include:
- Microfracture: Microfracture involves creating numerous tiny holes in the injured joint surface using a special tool called awl. The holes are made in the bone under the cartilage, called the subchondral bone. This creates new blood supply to the cartilage, which stimulates the growth of new cartilage.
- Drilling: This procedure is similar to microfracture where multiple holes are created in the injured joint area using a surgical drill or wires.
- Abrasion arthroplasty: This procedure is similar to drilling but involves the use of high-speed burs to remove the damaged cartilage.
- Autologous chondrocyte implantation (ACI): This is a two-step procedure, where the healthy cartilage cells are removed from the non-weight-bearing joint, grown in the laboratory and then implanted in the cartilage defect during the second procedure. During this procedure, a patch is harvested from the periosteum, a layer of thick tissue that covers the bone, and is sewn over the defective area using fibrin glue. The new cartilage cells are then injected under the periosteum into the cartilage defect to allow the growth of new cartilage cells.
- Osteochondral autograft transplantation: In this procedure, plugs of cartilage are removed from the non-weight-bearing areas of your own knee and transferred to the damaged areas of the joint. This method is used to treat smaller cartilage defects since the graft that is taken from your own body will be limited.
Following cartilage replacement, your doctor may recommend physical therapy to help restore mobility to the affected joint.
Osteochondral allograft transplantation: In this procedure, healthy cartilage tissue is taken from a donor from the bone bank. This is used as a graft and transplanted to the area of cartilage defect.