Cartilage Restoration

Recent advances in cartilage research and surgical techniques have made it possible to treat cartilage defects much more successfully than in the past. This article describes the basic anatomy of the knee in relation to cartilage injuries and discusses treatment options, which are now available to treat these injuries.

The knee joint is comprised of the surfaces of two bones, the femur (thigh bone) and the tibia (shin bone). The ends of these bones are coated with cartilage (called articular or hyaline cartilage), which makes these bones smooth. In fact, this cartilage makes these bones smoother than ice rubbing against ice. This cartilage is extremely important for pain-free, smooth knee motion. When this cartilage gradually wears away it is called osteoarthritis, which is what we normally think of as arthritis of old age. The other type of cartilage in the knee is the meniscus. There are two menisci in every knee, the medial and lateral menisci. These structures are extremely important in absorbing stress that travels through the knee when we walk. The menisci essentially function as shock absorbers. In the past, these menisci were removed when they were torn as they were thought not to be important. It was soon found that without a meniscus, the knee quickly went on to develop arthritis. It is now clear that the menisci perform a crucial role in the knee and all attempts are made to save them and as this article mentions, we now even have the ability to replace them.

When the knee is injured it is possible to damage either type of cartilage in the knee, the articular cartilage or the menisci. The result is often a painful knee that does not get better after an initial surgery. Frequently these injuries are associated with ligament tears such as a tear of the Anterior Cruciate Ligament (ACL). Obviously the pain caused by these cartilage injuries is of major concern to the patient. However, an even greater concern is the potential that these injuries can lead to arthritis at a young age. With recent advances in cartilage research we are now able to treat these injuries effectively.

One of the methods for treating these injuries is by using cartilage transplants. Essentially, a healthy piece of articular cartilage or meniscus or both is taken from a cadaver and used to replace the damaged cartilage in the patient’s knee. This can predictably improve the pain caused by these injuries. We are also hopeful that the development of arthritis can be slowed or perhaps even prevented. These procedures can often be performed on an outpatient basis and do involve a significant amount of rehabilitation after the surgery. Like other surgical procedures there are significant risks involved and not all patients are good candidates. The best candidate is the patient who has a painful knee with a discrete cartilage lesion that has not yet gone on to develop arthritis. Once arthritis develops, these cartilage transplants are of little help. Similar techniques can also be used to treat cartilage defects in the shoulder and other major joints as well.

In summary, cartilage restoration provides new methods of treating cartilage defects in the knee and other joints. While the field is still developing, and much more research is left to be done, we are optimistic that painful cartilage lesions can now be treated much more successfully and hopefully progression to arthritis can be delayed or perhaps even prevented.