Cartilage Injury

The knee joint is made up of the femur (thigh bone), tibia (shin bone), and patella (knee cap). The ends of the bones are lined with a specialized tissue called articular cartilage that creates a smooth gliding surface. The cartilage has no blood supply, so when the cartilage becomes injured, pieces can break off and the cartilage does not grow back. Sometimes, the bone underlying specific areas of cartilage looses its blood supply and becomes weak, causing the cartilage to break down.

When the cartilage becomes loose and breaks off, this creates loose fragments in the knee that can cause a catching sensation. The bone also gets exposed, which causes inflammation, swelling, and pain.

When the cartilage breaks down more diffusely, this is called arthritis; however, when patients are young and the cartilage damage is localized, there are several options to restore the cartilage to the affected area of the joint. This causes cartilage to regrow over the defect. While the cartilage is generally not as healthy and thick as normal, it provides a new gliding surface that results in less catching and pain. These treatments continue to evolve as more research is completed. In all cases of cartilage injury, it is important to evaluate the alignment of the knee joint as misalignment can cause overload of the painful part of the knee and can be the cause of the cartilage injury. If misalignment is discovered, additional procedures might be needed to correct it.

  • Symptoms

  • Treatment


  • Knee buckling
  • Catching sensation in the knee
  • Knee pain
  • Knee swelling
  • Knee stiffness and decreased range of motion due to pain and swelling

Frequently Asked


How do I know if I have a cartilage injury?

Patients with a cartilage injury often have painful catching and swelling in the knee. The pain is usually localized to inside, outside, or front of the knee. After taking a detailed history, performing a thorough exam, and looking at knee X-rays, an MRI is often ordered. An MRI allows for evaluation of the soft tissue structures, such as the menisci and cartilage.

How do I know if I need surgery or can just manage with conservative treatment?

If you have persistent pain and catching in the knee despite more conservative treatments, then you will most likely benefit from surgery. Surgery is recommended for athletes and younger patients to prevent further injury to the cartilage.

Can I have a cartilage restoration procedure if I have arthritis?

Generally, no. Cartilage restoration is reserved for more localized defects. Arthritis implies more diffuse breakdown of the cartilage in the knee and requires more extensive surgical intervention (such as a total knee replacement) if patients have failed more conservative treatment.

What are the risks associated with not treating my cartilage injury?

The most common risks are stiffness, persistent pain, and weakness from decreased use of the knee. Some cartilage injuries do not cause pain and do not require treatment.