Osteochondritis Dissecans

Overview

Osteochondritis dissecans (OCD) is a joint condition in which a small area of bone just beneath the cartilage surface loses its blood supply. Without adequate blood flow, the bone weakens and, in some cases, the affected bone and the cartilage covering it can crack and partly or fully separate from the surrounding healthy bone.

OCD most often affects the knee, but it can also occur in the elbow, ankle, and other joints. It is most common in active children and adolescents whose bones are still growing, though adults can be affected too. When caught early, especially in younger people with growing bones, OCD often heals on its own with rest. More advanced cases may need surgery.

Symptoms

Symptoms depend on which joint is involved and how advanced the condition is. They tend to develop gradually and may include:

• Pain brought on or worsened by physical activity, such as climbing stairs, running, or playing sports.
• Swelling and tenderness around the affected joint.
• Joint locking or catching, a sensation that the joint sticks or gets stuck in one position, which can happen if a loose fragment is present.
• Giving way or weakness, a feeling that the joint may buckle.
• Reduced range of motion, with difficulty fully straightening or bending the joint.

In the early stages, pain may be mild and noticeable only with vigorous activity. Locking and catching usually suggest a more advanced lesion with a loose piece of bone or cartilage.

Causes

The exact cause of osteochondritis dissecans is not fully known. It is thought to result from a reduction in blood supply to a small area of bone beneath the joint surface. Factors that may contribute include:

• Repetitive stress and overuse of a joint, especially in young athletes who train intensively.
• Minor repeated injuries to the joint over time.
• Genetic factors, as OCD sometimes runs in families and can affect more than one joint.
• Differences in bone development during periods of rapid growth.

Most likely, a combination of these factors leads to the area of bone losing its blood supply and beginning to separate.

Risk Factors

Several factors raise the likelihood of developing OCD:

• Age: It is most common between about 10 and 20 years of age, during periods of active bone growth.
• High activity level: Children and teens involved in repetitive, high-impact sports such as basketball, gymnastics, soccer, and throwing sports are at greater risk.
• Sex: It has traditionally been more common in males, although the gap has narrowed as more girls participate in competitive sports.
• Family history of the condition.

Diagnosis

Diagnosis begins with a physical examination, during which the clinician checks the joint for tenderness, swelling, and limits in movement, and asks about activity and symptoms. Imaging confirms the diagnosis and shows how advanced the lesion is:

• X-rays can reveal bone changes and the location of a lesion.
• MRI provides detailed images of bone and cartilage, helps determine whether a fragment is stable or loose, and is useful for planning treatment.
• CT scans may be used in some cases for additional detail.

Identifying whether the fragment is still attached and stable is key to deciding between non-surgical and surgical treatment.

Treatment

Treatment depends on the person's age, the joint affected, and whether the fragment is stable. Many children and teens with stable lesions heal without surgery:

• Rest and activity changes: Avoiding the activities that cause pain, sometimes for several weeks to months, allows the bone to heal. A brace, crutches, or temporary immobilization may be recommended.
• Physical therapy: Once healing begins, exercises restore strength, flexibility, and range of motion.
• Surgery: If the fragment is loose or detached, if symptoms persist despite rest, or in adults whose bones have stopped growing, surgery may be needed. Procedures can involve drilling to stimulate blood flow, fixing the fragment in place, or removing or replacing damaged tissue.

Early treatment improves the chance of full recovery and helps protect the joint over the long term.

Prevention

Because the exact cause is uncertain, OCD cannot always be prevented, but some steps may lower the risk of joint overuse injuries in young athletes:

• Avoid overtraining and allow adequate rest between intense sessions.
• Use proper technique and appropriate equipment for the sport.
• Build strength and flexibility gradually and warm up before activity.
• Take joint pain seriously and rest rather than playing through it, which can prevent a minor problem from worsening.

When to See a Doctor

See a healthcare provider if a child, teen, or adult has joint pain that:

• Persists or worsens with activity.
• Is accompanied by swelling, locking, catching, or a feeling that the joint may give way.
• Limits movement or interferes with sports and daily activities.

Early evaluation is important because a stable lesion in a young person often heals well with rest, while a delayed diagnosis can allow the fragment to loosen and may lead to longer-term joint problems. Prompt assessment helps protect the joint and guide the right treatment.

Related Topics

Frequently Asked Questions

References

1. Mayo Clinic. Osteochondritis dissecans.
2. American Academy of Orthopaedic Surgeons (OrthoInfo).
3. MedlinePlus, U.S. National Library of Medicine.
4. Nationwide Children's Hospital.