The Osteochondral Allograft Transplantion Surgery, commonly known as OATS, replaces damaged cartilage in the knee with healthy cartilage from a donor, relieving pain and restoring movement and function to the joint. A mosaicplasty is the name for a general procedure that treats severe cartilage damage, and the OATS procedure is a type of mosaicplasty.
Cartilage, or chondral, damage is known as a lesion and can range from a soft spot on the cartilage (Grade I lesion) or a small tear in the top layer to an extensive tear that extends all the way to the bone (Grade IV or "full-thickness" lesion). Sometimes a piece of cartilage breaks off and causes more damage to the cartilage and bone as it is ground in the joint.
The OATS Procedure
The OATS procedure is a treatment option focusing on biologic joint preservation. It involves the repair of damage to a specific joint for patients who do not yet need or wish to delay joint replacement surgery. Joint preservation procedures are most often performed on patients with arthritis, chronic injuries and other joint-related conditions.
While cartilage is essential for ensuring smooth, painless movement of the joints, some areas have a more critical need for the support and cushioning provided by the cartilage. During the OATS procedure, small plugs of healthy cartilage are taken from a donor and transferred to the area of damaged cartilage. In other forms of the procedure, cartilage may be removed from the patient’s own joints. However, allograft means that the cartilage comes from a donor individual instead.
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 small plugs of healthy cartilage may not provide enough material to completely rebuild the cartilage of the joint.