What is osteochondritis dissecans?
Osteochondritis dissecans (OCD) is a joint disorder in which a loose piece of bone and cartilage separates from the end of the bone due to presumed lack of blood flow. The fragment may stay in place (stable) or loosen (unstable) and even fall into the joint space, causing pain and mechanical symptoms. Although anyone can develop OCD, it is most common in children and adolescents who are highly active in sports. It typically affects the knee, elbow or ankle.
What causes osteochondritis dissecans?
The cause of osteochondritis dissecans is unknown. It is possible that repetitive trauma – small, multiple stresses over time – might cause damage to the bone and disrupt the blood supply. This type of overuse injury often occurs in young athletes. Other causes may include a genetic predisposition, rapid growth or abnormal bone formation.
What are the symptoms?
Pain, swelling and stiffness of the affected joint are the most common symptoms of osteochondritis dissecans. Other signs include:
- A popping sensation
- Soreness or tenderness at the joint line
- Difficulty straightening the joint fully
- A feeling of locking or giving way
- Fluid collection in the joint
Because symptoms of OCD often resemble those of other joint injuries, it's important to consult a qualified physician for a diagnosis.
How is osteochondritis dissecans diagnosed?
In addition to a physical examination and medical history, your physician might order an X-ray or MRI to evaluate the size and location of the OCD lesion.
What is the treatment?
In most cases, OCD injuries in children and teens heal on their own, especially if the body is still growing. Resting and avoiding vigorous sports until symptoms resolve will often relieve pain and swelling. Your physician may recommend crutches, splinting or casting for a short period of time.
If these conservative treatments fail to relieve symptoms, or if the lesion is unstable, detached or very large, surgery may be recommended. The type of surgery depends on the size and stage of the injury, as well as the patient's age and bone maturity.
The most common surgical technique is arthroscopy, a minimally invasive procedure in which the surgeon makes several small incisions and uses a small video camera (called an arthroscope) to see inside the joint. Tiny instruments are used to drill the stable symptomatic fragments or reattach the loose fragment and secure it with pins or screws. Dislodged fragments typically require removal with the possible need for cartilage and bone reconstruction if it is large.
Rehabilitation following surgery includes physical therapy to restore strength and stability to the affected joint. Most people are able to return to activities and sports within six months.