Knee > Osteochondral Defect

What is Osteochondral Defect?

The word osteochondral refers to anything relating to cartilage and bone. Your thighbone (femur), shinbone (tibia), and kneecap (patella) fit tightly together and move smoothly because the bone surface is covered with a thick coating of articular (hyaline) cartilage. An osteochondral defect is any type of damage to articular cartilage and underlying (subchondral) bone. Usually, osteochondral defects appear on specific weight-bearing spots at the ends of the thighbone and shinbone and the back of the kneecap. Osteochondral defects can range from:

   Roughened cartilage that causes slight pain.

   Small bone and cartilage fragments that hinder movement.

   Complete cartilage loss that leaves your bones grinding against each other.


Twisting forces combined with direct impact, like being tackled in football, commonly cause osteochondral defects. Sports that put you at risk of accidental collisions and require quick changes of direction, like soccer, basketball, and skiing, may put you at risk of damage to your articular cartilage. Osteochondral defects frequently accompany injuries that twist or tear other knee structures, such as ligaments and meniscus cartilage. Articular cartilage also tends to wear out with overuse. Many osteochondral defects in older active people are caused by slow cartilage deterioration.


Like arthritis, osteochondral defects generally continue to spread unless they are treated. Your articular cartilage has no direct blood supply and usually cannot heal on its own. Osteochondral defects may deteriorate your articular cartilage until bones are grinding against each other and your knee joint becomes permanently deformed. Depending on the grade of your articular cartilage damage caused by osteochondral defects, the following treatments are generally prescribed:

   Grade 1 - Cut back on sports activities and possibly a cast to prevent movement.

   Grade 2 - Arthroscopic drilling of frayed cartilage.

   Grade 3 - Removal of damaged bone and cartilage and possible transplant of new tissue.

In the case of chip fractures, physicians may suggest arthroscopic surgery to fix the chipped piece back into its original position. The links to the left describe standard osteochondral defect treatments in detail.

Orthopedic Evaluation [top]

There are usually three parts to an orthopedic evaluation: medical history, physical examination, and tests your physician may order.


our doctor will likely ask you when you noticed your knee pain, how it has been feeling since the pain began, and if your knee has been previously injured. Physicians also typically ask about other conditions, such as diabetes and allergies, and medications currently being taken. The doctor may also ask about your physical and athletic goals - information that will help him decide what treatment might be best for you in achieving those goals.


A physician usually can make an early assessment of an injury by feeling around the area. While asking you questions to pinpoint your pain, physicians typically test ligament and tendon strength by checking your knee's range of motion. To test for osteochondral defects, physicians may extract a sample of fluid from your swollen knee with a small needle. Damage to the bone and cartilage may cause a certain amount of blood and fatty tissue to appear in your knee fluid.


Should your physician require a closer look, these tests may be conducted:

   X-rays taken from different angles can sometimes show signs of loose bodies, small fractures, or other bone damage. X-rays typically do not provide a good view of articular cartilage.

   MRI (magnetic resonance imaging), CT scan (commonly referred to as a CAT scan), or bone scan may be used to see if your pain is due to bone, cartilage, or muscle problems. Results from MRI, CT scans, and bone scans are usually available in two days.

   Arthroscopy, in which the doctor inserts a tiny camera into your knee, may be used to determine the diagnosis in more detail. This is done on an outpatient basis and usually does not require a hospital stay.

Because some osteochondral defects develop slowly, you may have recurring mild pain and swelling even though imaging techniques may show no signs of cartilage or bone damage. Your physician may need to view multiple images to compare over time to reach a diagnosis.


   Imaging technique

Arthroscopic Reduction and Fixation
Cartilage Transplantation
Arthroscopic Microfracture Drilling

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