ConditionBones, joints & muscles
Osteochondral Fracture
An osteochondral fracture is an injury in which a piece of joint cartilage and the bone directly beneath it is cracked or broken off, usually in the knee, ankle (talus) or elbow. It typically happens with a twisting injury, a kneecap dislocation or an ankle sprain. It causes pain, swelling, and sometimes locking or catching if a loose fragment moves within the joint. It is easily missed on X-rays, so MRI is often needed. Small stable lesions may heal with rest, while displaced fragments usually need surgery.
Also called: Osteochondral lesion, osteochondral defect, chondral fracture (cartilage only), osteochondral injury
At a glance
- What it is
- A break through joint cartilage and the underlying bone.
- Common sites
- Knee (kneecap and femur), ankle (talus dome), elbow (capitellum).
- Causes
- Kneecap dislocation, twisting knee injury, ankle sprain, direct impact.
- Symptoms
- Pain, swelling (often with blood in the joint), catching, locking, giving way.
- Diagnosis
- X-ray may miss it. MRI or CT shows the lesion.
- Treatment
- Rest and protected weight bearing for stable lesions. Surgery to fix or remove loose fragments.
When to get help
Call 911 or go to the ER
- An obviously deformed joint, or a cold, pale or numb limb after injury
See a doctor within a day or two
- Rapid joint swelling within hours of an injury, especially after a "pop" or kneecap dislocation
- A joint that locks and cannot be straightened
- Inability to bear weight after an ankle or knee injury
Book a routine appointment
- An ankle sprain that is still painful, swollen or catching after 6 weeks
- Recurrent swelling, clicking or giving way in a knee or ankle after an old injury
- Deep, aching joint pain with activity months after a sprain
Usually safe to manage at home
- Rest, ice, compression and elevation in the first days after a minor sprain while awaiting assessment
What happens in an osteochondral fracture
Joint surfaces are covered by smooth articular cartilage that sits on a layer of bone (subchondral bone). A shearing, twisting or impact force can crack through both layers. The fragment may:
- stay in place (stable, non-displaced)
- partly detach (unstable)
- break free as a loose body that floats in the joint
Cartilage has a poor blood supply and limited ability to heal, so damaged areas can progress to early post-traumatic arthritis if untreated.
Causes and common sites
| Site | Typical injury | Notes |
|---|---|---|
| Kneecap and outer femur | Patellar dislocation | Occurs in a significant proportion of kneecap dislocations, usually in teens and young adults |
| Femoral condyle (knee) | Twisting injury, ACL tear | Often seen with ligament and meniscal tears |
| Talus (ankle) | Ankle sprain or ankle fracture | Common cause of persistent pain after a "simple" sprain |
| Capitellum (elbow) | Falls, repetitive throwing | Seen in young athletes |
Osteochondral fracture vs osteochondritis dissecans
Osteochondritis dissecans (OCD) is a related condition, mainly in children and teens, in which a piece of bone and cartilage gradually loses its blood supply and separates, often from repetitive stress rather than a single injury. An osteochondral fracture is caused by an acute injury. Imaging and treatment are similar.
Symptoms
- joint pain, often deep and worse with weight bearing or activity
- swelling soon after injury, often with blood in the joint (hemarthrosis)
- stiffness and reduced range of motion
- catching, clicking or locking if a loose fragment moves
- a feeling of giving way
- in the ankle, persistent pain months after a sprain
Diagnosis
- examination: swelling, tenderness, range of motion, ligament stability
- X-rays: may show a bony fragment, but cartilage-only or small injuries are often invisible
- MRI: the best test to see cartilage, bone bruising, fragment stability, and associated ligament or meniscus injuries
- CT: shows bone fragment size and position for surgical planning
- arthroscopy: looking inside the joint with a camera confirms and treats the lesion
Treatment
Non-surgical
For small, stable, non-displaced lesions, especially in children and teens:
- rest from impact activities
- protected weight bearing with crutches or a boot for several weeks
- a brace or cast in some cases
- physical therapy to restore motion and strength
- repeat imaging to confirm healing
Surgical
Surgery is usually recommended for displaced, unstable or large fragments, loose bodies, or lesions that fail to heal:
- fixation: reattaching the fragment with screws, pins or bioabsorbable implants, best when the fragment includes good bone and surgery is done early
- removal of small loose fragments
- marrow stimulation (microfracture): creating small holes in the bone to stimulate repair tissue
- cartilage restoration: osteochondral autograft (plug transfer) or allograft, or autologous chondrocyte implantation for larger defects
- treating associated injuries, such as stabilizing the kneecap or repairing ligaments
Recovery
Recovery depends on the site, size and treatment. Non-surgical healing often takes 6 to 12 weeks. After fixation or cartilage restoration, return to sport commonly takes 4 to 12 months. Physical therapy is essential.
Outlook
Small, well-treated lesions often heal well. Larger lesions and those found late carry a higher risk of ongoing pain and early osteoarthritis. Young patients generally heal better than adults.
Frequently asked questions
What is an osteochondral fracture?
An osteochondral fracture is a break involving joint cartilage and the bone directly underneath it, usually caused by a twisting injury, impact or kneecap dislocation. It most often affects the knee, ankle or elbow and can leave a loose fragment inside the joint.
What are the symptoms of an osteochondral lesion?
Symptoms include joint pain, swelling, stiffness, catching, clicking, locking and a feeling of the joint giving way. In the ankle, a common sign is ongoing pain and swelling long after an ankle sprain should have healed.
Why didn't my X-ray show the fracture?
Cartilage does not show on X-rays, and small bone fragments can be hidden. MRI is much better at detecting osteochondral injuries, bone bruising and associated ligament damage. Doctors often order MRI when symptoms persist despite a normal X-ray.
Does an osteochondral fracture need surgery?
Not always. Small, stable lesions, particularly in young people, may heal with rest and protected weight bearing. Displaced or unstable fragments, loose bodies, and larger lesions usually need surgery to fix, remove or replace the damaged area.
How long does it take to recover from an osteochondral fracture?
Non-surgical healing typically takes 6 to 12 weeks. After surgery, recovery and return to sport commonly take 4 to 12 months depending on the procedure. A structured physical therapy program improves results.
Sources
This guide was written from current patient and clinical guidance, including:
- American Academy of Orthopaedic Surgeons (OrthoInfo): Osteochondritis dissecans and cartilage injuries
- American Orthopaedic Foot & Ankle Society: Osteochondral lesions of the talus
- International Cartilage Regeneration & Joint Preservation Society: Cartilage injury classification
- Radiopaedia: Osteochondral fracture
- American Academy of Family Physicians: Evaluation of acute knee injuries