Osteochondral Fracture

Overview

Joint surfaces are covered by smooth articular cartilage, which lets bones glide over one another, and supported by the bone just underneath (the subchondral bone). An osteochondral fracture is an injury that breaks through both the cartilage and this underlying bone.

These injuries are most common in the knee, ankle, and elbow. Sometimes a fragment of cartilage and bone breaks loose inside the joint, which can catch or lock the joint. Because cartilage heals poorly, osteochondral fractures need proper assessment to protect long-term joint health.

Symptoms

Symptoms vary with the joint and severity but often include:

• Joint pain, usually worse with movement or weight-bearing
• Swelling that may develop soon after the injury
• Stiffness and reduced range of motion
• A catching, clicking, or locking sensation if a fragment is loose
• A feeling that the joint gives way

An acute injury may follow a clear event such as a twist, fall, or dislocation, with immediate pain and swelling.

Causes

Osteochondral fractures result from forces that shear or compress the joint surface, such as:

• A twisting injury during sport
• A direct blow or fall onto a joint
• A joint dislocation, such as the kneecap or ankle, that scrapes the cartilage as it moves
• Repeated impact in some cases, contributing to a related condition called osteochondritis dissecans

The exact injury depends on the direction and force of the load across the joint at the moment of injury.

Risk Factors

• Participation in contact and pivoting sports
• A previous joint dislocation, such as patellar or ankle dislocation
• Joint instability or ligament injuries
• Younger, active age groups for some types
• High-impact activities and falls

Diagnosis

Diagnosis combines the injury history, examination, and imaging:

• X-rays: Can show a bone fragment, but small cartilage injuries may not appear.
• MRI: The most useful test, showing the cartilage, the bone underneath, swelling within the bone, and any loose fragment.
• CT scan: Helps define the bony part of the fracture and plan surgery.
• Arthroscopy: A keyhole camera can both confirm the injury and treat it.

Treatment

Treatment depends on the size and stability of the fragment, the joint involved, and the person's age and activity.

• Non-surgical care: Small, stable injuries may be treated with a period of reduced weight-bearing, bracing, and physical therapy to allow healing.
• Surgery: A loose or large fragment may be fixed back in place, removed, or treated with cartilage repair or restoration techniques. These are often done arthroscopically.

Rehabilitation gradually restores motion and strength. Because cartilage has limited healing capacity, untreated injuries can raise the long-term risk of joint wear, so appropriate treatment matters.

Prevention

• Use proper technique and protective gear in sport
• Strengthen the muscles around the knee, ankle, and other joints for stability
• Address joint instability and recurrent dislocations promptly
• Warm up and progress training gradually

When to See a Doctor

See a doctor after a joint injury if you have lasting pain, swelling, or stiffness, or if the joint catches, locks, or gives way. These can indicate an osteochondral fracture that benefits from imaging.

Seek urgent care for severe pain, marked deformity, inability to bear weight, or a joint that appears dislocated, as these need prompt evaluation.

Related Topics

Frequently Asked Questions

References

1. American Academy of Orthopaedic Surgeons (OrthoInfo). Cartilage injuries of the knee.
2. Mayo Clinic. Cartilage and joint injuries.
3. MedlinePlus, U.S. National Library of Medicine. Fractures.
4. National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS).