Osteochondritis dissecans (OCD) is a condition in which a piece of cartilage and a thin layer of bone in a joint come loose from the end of a long bone. OCD most commonly occurs in the knee, although it can also occur in other joints such as the ankle and elbow. OCD can cause severe limitation in function of adolescents as a result of knee soreness and locking, and it can be treated either non-operatively or surgically depending on the severity of the case.
The precise cause of OCD is unknown, but there are a number of risk factors that it is associated with including age, sex, and genetics. OCD most often affects adolescents between the ages of 10 and 20 years, and males are more likely to suffer from OCD than females. Some people may also be genetically predisposed, as some children can develop OCD in several different joints. Multiple, repetitive trauma to the joints over time may also increase the likelihood of OCD. A limited blood supply to joint cartilage reduces the body’s ability to heal injuries and likely contributes to the loosening and separation of cartilage and bone that defines OCD.
Adolescents with OCD typically have soreness and pain in the affected knee triggered by physical activity. They may also feel joint locking or popping, decreased range of motion, and joint weakness. A patient with such symptoms should see an orthopedic surgeon or a primary care physician with an expertise in sports medicine. The physician will likely order an MRI to identify loose bone fragments in the joint and to confirm the diagnosis of OCD.
If OCD is confirmed by a physician, there are a number of treatment options available to reduce or eliminate the symptoms. Mild cases of OCD may heal by themselves, especially in skeletally immature children that are still growing, so simply resting the joint and restricting weight bearing may be recommended in these situations. Physical therapy is another non-operative treatment option for stable OCD lesions.
Surgical treatment is recommended for more severe cases of OCD in which the cartilage and bone are completely detached or in mild cases in which non-operative treatment fails and symptoms persist for many months. Surgery to treat OCD is often arthroscopic, meaning that it is a minimally invasive procedure performed by inserting a small camera into the joint through a small incision. Surgery may involve drilling into the cartilage to re-establish the blood supply and promote healing to the injured area, and it also may involve fixation of the loose bone and cartilage fragment to the end of the bone.
The decision to undergo surgical treatment for OCD depends on the age of the patient, the severity and duration of symptoms, and the effectiveness of non-operative treatment. If the OCD lesion is “unstable” on MRI, surgery is the best option to reattach the fragment so it does not break off into the knee joint. There are many factors that affect decision making and treatment is individualized for each patient.