OCD

Knee joint in a juvenile, showing a dark area of osteochondritis dissecans damage in the bone and cartilage of the femur.

What is an osteochondral defect?

An osteochondral defect is a circumscribed area of joint damage, where the rest of the joint is mostly in good condition, such as might follow from a blow on the knee.

What is osteochondritis dissecans

Osteochondritis dissecans is a particular type of osteochondral defect caused by a failure of blood supply to a small area, which local loosening of a small chunk of bone and cartilage in a similar way