Children are involved in sports more than ever before. Year-round practice and competitive play have increased the number of orthopedic conditions and injuries reported. One of those conditions is the condition you mentioned: osteochondritis dissecans (OCD) or JOCD when juveniles (children and teens) are affected.
OCD mostly affects the femoral condyles of the knee. The femoral condyle is the rounded end of the lower thighbone, or femur. Each knee has two femoral condyles, referred to as the medial femoral condyle (on the inside of the knee) and the lateral femoral condyle (on the outside). Like most joint surfaces, the femoral condyles are covered in articular cartilage. Articular cartilage is a smooth, rubbery covering that allows the bones of a joint to slide smoothly against one another.
The problem occurs where the cartilage of the knee attaches to the bone underneath. The area of bone just under the cartilage surface is injured, leading to damage to the blood vessels of the bone. Without blood flow, the area of damaged bone actually dies. This area of dead bone can be seen on an X-ray and is sometimes referred to as the osteochondritis lesion.
The lesions usually occur in the part of the joint that holds most of the body’s weight. This means that the problem area is under constant stress and doesn’t get time to heal. It also means that the lesions cause pain and problems when walking and putting weight on the knee. It is more common for the lesions to occur on the medial femoral condyle, because the inside of the knee bears more weight.
Until recently, boys were affected more often than girls. But last year, over three million girls were participating in organized sports. And they are joining in at a much younger age. With year-round sports opportunities and increased frequency and intensity of practice and play, we can expect to see more of these types of injuries.
Prevention depends on identifying risk factors and modifying them. But right now, we only have guesses about what leads up to OCD. If it were just the training and play schedule, then everyone would have this problem. But it’s not. So that means there are other influences. Genetics, growth spurts, bone abnormalities, and decreased blood supply are just a few possibilities.
Scientists are studying the problem and may be able to offer some insights in the near future. Until then, keep a record of each girl’s training schedule, number of minutes played each week, and amount of time engaged in other sports activities. It may be possible to look back at the records and find a common factor among those girls who develop OCD. Finding a way to prevent the problem becomes much easier when the causative risk factors are identified.