Osteochondritis dissecans is a joint condition where a small section of bone underneath the joint surface becomes damaged due to a loss of blood supply. Over time, this can affect the overlying cartilage – the smooth, protective tissue that helps joints move freely. In some cases, the affected piece of bone and cartilage may loosen or separate from the surrounding tissue, causing pain, swelling, and joint problems.
Osteochondritis dissecans most commonly affects the knee, particularly in children, teenagers, and young adults involved in sport. However, it can also occur in the ankle, elbow, and less commonly, other joints. Juvenile OCD (JOCD) can be distinguished from adult OCD by the presence of open growth plates. The condition often develops gradually and may initially be mistaken for a simple sporting injury or “growing pains” in children and adolescents.
Early diagnosis and appropriate management can help optimise healing and reduce the risk of long-term joint complications.
Key Facts
- The knee is the most commonly affected joint, particularly the medial femoral condyle. 🔗
- OCD is more common in young athletes involved in repetitive running, jumping, pivoting, or throwing sports. 🔗
- Approximately 50% to 67% of stable juvenile osteochondritis dissecans lesions heal successfully with non-surgical treatment, particularly in younger patients with good adherence to rehabilitation programs. 🔗
- Early diagnosis improves the likelihood of healing without surgery. 🔗
Risk Factors
- Participation in high-impact or repetitive sports.
- Rapid growth during adolescence.
- Previous joint injuries, particularly recurrent ankle sprains or knee injuries.
- Poor movement mechanics or landing technique, muscle weakness.
- Sudden increases in training intensity or volume with inadequate rest.
- Early sport specialisation with year-round participation in one sport.
Symptoms
- Joint pain felt during or after activity, particularly running, jumping, pivoting, or sport. The pain may initially come and go but can become more constant over time.
- Swelling after exercise or prolonged activity. In the knee, swelling may appear around the kneecap or along the joint line.
- Stiffness in the joint after periods of rest.
- Sensations of clicking, catching or even sudden locking of the joint.
- Weakness or instability. The joint may feel unreliable or “give way”, especially during sport or rapid direction changes.
Aggravating Factors
- Running, particularly on hard surfaces.
- Jumping and landing activities.
- Repetitive squatting or deep knee bending.
- Repetitive throwing or overhead activities (for elbow involvement).
- Heavy training loads with inadequate recovery.
Causes
The exact cause of osteochondritis dissecans is not fully understood, but several contributing factors are believed to play a role including:
- Repetitive joint stress: Sports involving running, jumping, pivoting, throwing, or gymnastics place high forces through growing joints.
- Reduced blood supply: The affected bone area may temporarily lose blood flow, reducing the bone’s ability to remain healthy and repair itself properly.
- Growth and development: The condition is more common during periods of rapid growth in adolescence. Growing bones may be more vulnerable to stress and injury.
- Genetics: Some evidence suggests a possible genetic component, particularly in families where multiple members are affected.
- Joint Alignment and Biomechanics: Abnormal movement patterns, muscle weakness, altered alignment, or poor landing mechanics may increase stress on certain areas of the joint.
- Previous injury: A history of joint trauma or repeated minor injuries may contribute in some individuals.
How Is It Diagnosed?
Diagnosing osteochondritis dissecans involves a combination of a thorough clinical assessment and medical imaging. Early diagnosis is important, as treatment is generally more successful before the lesion becomes unstable or separates from the surrounding bone.
A doctor or physiotherapist will ask about:
- The location and duration of symptoms
- Sporting participation and training loads
- Previous injuries
- Episodes of swelling, locking, or giving way
- Activities that aggravate or relieve symptoms
During the physical examination, they may assess:
- Joint tenderness
- Swelling or fluid within the joint
- Range of motion
- Muscle strength
- Walking and movement patterns
- Signs of joint locking or instability
While symptoms and physical examination may suggest osteochondritis dissecans, imaging is required to confirm the diagnosis and assess severity.
Investigations & Imaging
- Plain X-ray
- Can identify changes in the bone and help assess lesion size.
- MRI (Magnetic Resonance Imaging)
- Particularly useful because it shows cartilage health, bone swelling, and whether the fragment is stable.
- CT (computed tomography)
- Provide detailed bone imaging and may be used for surgical planning.
Grading / Classification
- Grade I (Stable Lesion)
- A small area of bone is affected, but the overlying cartilage remains intact and the lesion is stable. Symptoms are often mild, and non-operative treatment is usually successful.
- Grade II (Partially Stable Lesion)
- The cartilage may show signs of separation, but the fragment remains attached to the underlying bone. Healing is still possible with conservative management, although closer monitoring is often required.
- Grade III (Unstable Lesion)
- The bone and cartilage fragment has partially detached and is unstable, but remains within its original location. Symptoms such as pain, swelling, and joint catching are more common, and surgery may be considered.
- Grade IV (Detached Fragment)
- The fragment has completely separated from the surrounding bone and may become a loose body within the joint. This can cause locking, catching, and significant joint dysfunction. Surgical treatment is typically required.
Physiotherapy Management
The management of osteochondritis dissecans depends on several factors, including the individual’s age, symptoms, activity level, and whether the lesion is stable or unstable. The primary goals of treatment are to reduce pain, promote healing, restore joint function, and facilitate a safe return to activity. In many cases, conservative management is effective, particularly in children and adolescents with stable lesions, although surgery may be required for more advanced or unstable cases. A combination of activity modification, physiotherapy, and ongoing monitoring is often recommended to optimise outcomes.
Exercise
Exercise is an important part of the rehabilitation process for osteochondritis dissecans and is typically guided by a physiotherapist. Initially, exercises focus on maintaining joint mobility, reducing stiffness, and preserving muscle strength while minimising stress on the affected area. As symptoms improve and healing progresses, the program is gradually advanced to include strengthening, balance, coordination, and sport-specific exercises. The goal is to restore normal movement, improve joint stability, and safely return the individual to their usual activities while reducing the risk of re-injury.
Activity Modification
Reducing aggravating activities is often the first step. This may involve temporarily avoiding running, jumping, pivoting sports, heavy loading or throwing activities. Complete rest is not usually required, but reducing activities that place stress on the joint is important to support healing.
Bracing & Taping
Taping and bracing may be used to help manage symptoms and support the healing process in people with osteochondritis dissecans. Taping can provide symptom relief by improving joint support, reducing discomfort during activity, and assisting movement control. In some cases, bracing or temporary immobilisation may be recommended to reduce stress on the affected joint and protect the lesion while it heals. This may include the use of knee braces, walking boots, crutches, or other supportive devices, particularly for unstable lesions or following surgery.
Heat & Ice
Ice and compression may be used when knee is acutely aggravated to reduce swelling and pain in the joint.
Education
Patients should follow activity restrictions and rehabilitation recommendations to support recovery and prevent further joint damage. Any increase in pain, swelling, or joint symptoms should be discussed with their healthcare provider. Regular follow-up is important to monitor healing and guide a safe return to activity.
Surgery
Surgery may be considered when symptoms persist despite conservative management or when the affected area is unlikely to heal on its own. The aim of surgery is to reduce pain, improve joint function, and support healing. A rehabilitation program is important to help patients safely return to daily activities and sport.
Prognosis & Return to Activity
Prognosis is generally good, especially when diagnosed early and managed appropriately. Return to activity should be gradual and based on symptom resolution, functional recovery, and rehabilitation progress. Return to sport should occur only after clearance from the treating healthcare professional.
Complications
- Persistent joint pain can continue during sport, exercise, or everyday activities.
- Recurrent swelling may occur, particularly after physical activity.
- The affected bone and cartilage fragment may become loose and detach within the joint.
- A loose fragment can cause mechanical symptoms such as catching, clicking, or locking of the joint.
- Untreated or poorly healed lesions can increase the risk of developing joint issues later in life.
Preventing Recurrence
- Gradually increase training load, avoiding sudden increases in training intensity, frequency, or duration.
- Avoid overtraining by including regular rest days and vary activities to reduce repetitive stress on the same joint.
- Maintain good lower limb strength.
- Improve movement mechanics by training proper jumping, landing, running, and cutting techniques to minimise excessive joint loading
- Wear appropriate footwear that are suitable for your sport and playing surface.
- Return to sport gradually after injury.
When to See a Physio
- Joint pain that lasts longer than 1–2 weeks.
- Pain that returns every time you exercise.
- Swelling after activity.
- Clicking, catching, locking, or giving way of the joint.
- Reduced ability to fully straighten or bend the joint.
- Difficulty running, jumping, squatting, or climbing stairs.
- Ongoing pain after surgery or a period of rest.