Knee Joint Cartilage Defects: Medium Cartilage Defect Replacement Animation

Knee Joint Cartilage Defects: Medium Cartilage Defect Replacement Animation

Speaker1: This animation demonstrates an osteochondral allograft transplantation, or OATS procedure, used to treat a medium cartilage defect in the knee. In this procedure, a cartilage graft is taken from a cadaver donor and placed over 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 medium cartilage defect on the inner end of the femur.

First, a sizing instrument is used to measure the cartilage defect. Here, we see the inner half of the bottom of a femur covered in articular cartilage from a cadaver donor. The same sizing instrument is used to mark out the size of the cartilage graft that will be needed to cover the cartilage defect.

The sizing instrument is placed over the cartilage defect again, and a drill pin is inserted into the thigh bone through the instrument. The area around the defect is marked out, and an instrument of the same size, called a scorer, is placed over the drill pin and used to make a round cut in the cartilage down to the bone.

Speaker1: Then, a reamer is placed over the drill pin and used to drill out the round section of cartilage and bone. This makes a hole, or socket, that will allow a cartilage graft to neatly fit into.

A dilator is placed over the exposed bone and tapped in place to finalize the shape of the socket. Another sizing instrument is used to measure the depth of the socket, which will help determine the correct size of the donor graft.

The donor femur is secured in a workstation, and a drill is used to cut out a piece of cartilage from the femur. A saw is then used to remove the underside of the cartilage with the attached bone, and the graft is removed.

The graft is measured and shaped to match the size of the prepared socket. The graft may be soaked in a solution made from the patient’s own blood or blood components, which are rich in compounds that can help improve healing.

In this procedure, bone gel is placed over the exposed bone in the socket to further help with healing. The graft is positioned over the prepared socket and tapped into place. The procedure is now complete.