OATS (Osteochondral Autologous Transfer Surgery)
Osteochondral Autologous Transfer Surgery (OATS) is a surgical procedure to treat isolated cartilage defects which are usually no more than 10 to 20mm in size. The procedure involves transfer of cartilage plugs taken from non-weight bearing areas of the joint and transferring them into the damaged area of the joint.
This procedure is not indicated for wide spread damage of cartilage as seen in osteoarthritis.
The procedure is usually performed using arthroscopy or ‘key-hole surgery’. During the procedure, the area of damaged cartilage is prepared using a coring tool which makes a perfectly round hole in the bone in the area of damage. The hole is drilled to a size that fits the planned plug. Next the plug of normal cartilage/bone is harvested from a non-weight bearing area of the knee and is then implanted into the hole that was created in the damaged area. The size of the plug used will be slightly larger than the hole so that it obtains a ‘press-fit’ in its new position. This procedure allows the newly implanted bone and cartilage to grow in the damaged area.
Possible complications of OATS include ‘donor site’ problems causing pain, avascular necrosis, and fracture. Other complications such as haemarthrosis, effusion and pain may be experienced. Following OATS procedures, rehabilitation is recommended by use of crutches and limiting the range of motion with a brace.