Cartilage Restoration

The ends of our bones are covered with articular cartilage which is allows the bones to glide easily over each other providing smooth and effortless motion. When articular cartilage is damaged by injury, disease and normal wear and tear, it causes inflammation, pain and stiffness and compromises joint function. Importantly, if the defects are not treated, they can lead to degenerative joint disease and ultimately early-onset osteoarthritis.

What is a chondral defect?

Localized damage to the articular cartilage is called a chondral defect or chondral lesions. Chondral defects are graded by their severity with the mildest damage being a Grade I, and the most severe damage being a Grade IV.

Chondral defects are common injuries affecting young people, and 5-10% of people over the age of 40. A localized injury can cause pain, stiffness, swelling and catching or locking in the knee joint due to a loose fragment of cartilage.

What causes a chondral defect?

A cartilage defect frequently results from an acute trauma such as a fall or a direct blow to the knee. It can also result from a twist of the knee, or a sudden change of direction. The trauma that causes an ACL tear is also associated with chondral defects.

Isolated chondral defects of the knee are particularly difficult to treat due to the limited healing potential of cartilage. Defects can be especially challenging in younger patients whose only other treatment options may be partial and total knee replacement. Fortunately, numerous minimally invasive surgical techniques have been developed to address these defects and help younger patients avoid knee replacement.

How are these defects diagnosed?

Symptoms alone are insufficient to diagnose the defects since the same symptoms are common in many knee conditions and injuries. During your orthopedic consultation with Dr. Tom Hackett, he will ask about your symptoms and the injury that caused the problem, as well as your goals for future activity such as sports participation. He will conduct a physical exam including testing range of motion, knee stability and gait.

Dr. Hackett will order x-rays to evaluate the joint bones and to reveal the presence of arthritis. An MRI or CT scan will be ordered to view the soft tissues including the cartilage, but the optimal tool for diagnosis of chondral defects is arthroscopy. It allows him to be able to view and treat the defects at the same time.

What are the treatment options for chondral defect?

The size and location of the defect and the age and activity level of the patient are determinative.  Initially Dr. Hackett may recommend a trial of conservative management to include anti-inflammatory medications, rest, icing, compression and physical therapy. Steroid and hyaluronic acid injections may be recommended to improve pain and function. Conservative management treats the symptoms only. If this fails to improve symptoms the defect itself must be treated.

To treat the defect, surgery will be necessary. Numerous surgical techniques have been developed to address these defects with minimally invasive arthroscopy.

• Arthroscopic debridement is designed to improve pain and function by removing loose pieces of cartilage that can cause clicking and locking in the joint. It can take up to six weeks to recover. A recent study reports that arthroscopic debridement for chondral defects is beneficial notwithstanding the size of the defect. Another recent study reports that arthroscopic debridement of articular cartilage defects provides good to excellent short – and medium-term postoperative outcomes, especially functional improvement.
• Arthroscopic microfracture is a procedure to stimulate the bone to generate new cartilage. The outer layer of bone is penetrated to expose the marrow where the new stem cells can fill in the defect by growing new cartilage.  It is a safe and effective first-line treatment for young and middle-aged individuals who otherwise have healthy cartilage. However, newer research reports that microfracture paired with cartilage augmentation provides superior results.  Postoperative physical therapy is necessary to restore weight bearing without pain.

Dr. Thomas Hackett specializes in complex knee conditions, arthroscopy and the OATS and ACI procedures, as well as stem cell transplants.

• Cartilage transfer. Osteochondral (bone and cartilage) autograft transfer system or OATS has been shown to be superior to microfracture but requires expert technical skills. OATS provides immediate filling of defects with the transfer of cartilage harvested from non-weightbearing areas of the joint.
• Cartilage implants. Autologous chondrocyte implantation (ACI) has been shown to result in good repair but is a two-stage procedure- harvesting the cells, culturing the cells and implanting the cells in the defects. Another technique involves growing the cells on a collagen scaffold which is then implanted into the defect. This involves significant expertise.
• Stem Cell transplants. Stem cells can divide and differentiate into many different types of cells including cartilage cells. Derived from bone marrow they can injected into the joint and provide improvements in pain and quality of life. They can also be put on a scaffold and transplanted into the joint.

When you or a loved one suffers with a painful knee contact an expert- Dr. Thomas Hackett who has offices in Vail Colorado. You will receive expert care so you can return to the activities that make life enjoyable.