Knee Joint Cartilage Defects: Small Cartilage Defect Replacement Animation

Knee Joint Cartilage Defects: Small Cartilage Defect Replacement Animation

This animation demonstrates an osteochondral autograft transplantation, or OATS procedure, used to treat a small cartilage defect in the knee. In this procedure, a cartilage graft, called a plug, is taken from a healthy non-weight-bearing part of the knee and transferred to the area of the patient’s cartilage defect.

Here, we see a right knee, with the inner side of the knee on the right side of the screen. The knee is bent to expose the surfaces at the end of the femur, or thigh bone. Here, we see a small cartilage defect on the inner end of the femur. First, a sizing instrument is used to measure the cartilage defect. Then, a graft harvesting instrument of the same size is placed over a non-weight-bearing part of the knee. The harvesting instrument is tapped into the cartilage and underlying bone, and the cartilage graft is removed.

Next, a drill pin is inserted into the cartilage defect and a reamer is placed over the drill pin to drill out a round section of cartilage and bone. This makes a hole, or socket, that will allow the cartilage graft to neatly fit into. The drill pin and reamer are removed. The cartilage graft is shaped to the correct size, and a clear tube is placed on the end of the harvesting instrument. The cartilage graft is pushed out of the harvesting instrument to lay flush with the end of the plastic tube, which is placed over the socket made around the cartilage defect.

The graft is pushed out of the harvesting instrument to insert it into the socket and gently tapped in place. The area where the graft was removed can be filled with a donor plug from a cadaver. The procedure is now complete.