When there is a loss of blood supply to cartilage and the bone below that cartilage, it is known as Osteochondritis Dessicans. It is a joint condition that may lead to fragmentation or even a fracture.
The knee is the most common site for this condition to develop with 75% of cases occurring at the knee. Other sites include ankle, elbow, or hip.
The causes are not well understood.
The condition begins with dull aching in the knee which may occur for years, which is then aggravated by strenuous physical activity,