Osteochondral Allograft Transplantation
Osteochondral allograft transplantation surgery (OATS) is a procedure that replaces damaged cartilage in the knee with healthy cartilage from a donor, relieving pain and restoring movement and function to the joint. Cartilage is the smooth coating on the end of the bones that provides cushioning and support for comfortable and fluid movement of the joints. Cartilage damage may occur as a result of injury or degeneration and can lead to severe pain and arthritis. Damaged cartilage can eventually wear away and leave the bone unprotected. Because damaged cartilage normally does not heal well on its own, several surgical techniques have been developed to stimulate the growth of new cartilage.
The OATS techniques involve transplanting healthy cartilage from from a cadaver to a damaged joint, to stimulate the growth of new cartilage in a damaged area. When cartilage has been restored through the OATS procedure, it can help to delay or prevent the onset of arthritis. The OATS procedure is ideal for patients with small areas of cartilage damage that can be easily repaired with a graft. Widespread cartilage damage cannot usually be treated with this procedure, since the graft may not provide enough material to completely rebuild the cartilage of the joint.
The OATS Procedure
During the OATS procedure, small plugs of healthy cartilage are taken from a cadaver donor and transferred to the area of damaged cartilage. Prior to the procedure, the donor cartilage is sterilized and prepared, and tested for any possible disease transmission. The OATS procedure is performed while the patient is sedated under general anesthesia. During the procedure, very small incisions are made over the affected joint and an arthroscope, a tiny instrument with a light and camera, is inserted. The surgeon examines the interior of the joint and removes any debris. Additional tiny incisions are made to introduce the plugs of donor cartilage into the joint. The surgeon uses tools to create openings in the damaged areas of cartilage to exactly fit these plugs, then grafts them into place. After they have been transplanted, the incisions are sutured closed.
Risks of Osteochondral Allograft Transplantation
While the OATS procedure is considered a safe procedure, there are potential risks, which may include the failure of the donor cartilage to integrate completely with the patient's existing cartilage. Additional complications may include:
- Joint stiffness
- Tissue damage
There is also a minimal chance of contracting an infection or disease from the donor tissue. Patients should consider these risks before deciding to have the OATS procedure.
Recovery from Osteochondral Allograft Transplantation
After the OATS procedure, the joint is bandaged. Swelling is common and regular applications of ice are recommended. Medication may also be prescribed to treat pain. Following the procedure, individuals may use a continuous passive motion (CPM) machine to keep the joint moving and to alleviate joint stiffness. Patients are typically advised to rest the affected joint for one to two weeks after the surgery. Most patients will use crutches for 6 to 12 weeks after surgery before they can successfully bear weight on the joint again. A physical therapy program helps to restore mobility and improve strength and flexibility of the affected joint. While recovery times vary, exercise and and regular activity can normally resume 2 to 3 months after the OATS procedure.