Growing a New Knee

Cartilage does not naturally regenerate in the body, which is bad news for anyone who damages a joint. Even small tears tend to worsen over time, causing extreme pain and reducing mobility.

Once arthritis sets in, only a total joint replacement can alleviate the problem. A new procedure developed by Swedish researchers clones cartilage cells, which are introduced into the damaged area and regenerate healthy tissue.

Here’s how it works in repairing a damaged knee joint.

* First surgery:

Healthy cartilage cells are removed from the joint.

In the laboratory, the cells are cultured. It takes two to three weeks to grow enough replacement cells.

* Second surgery:

An incision exposes the injured portion. Damaged cartilage is removed. The area is cleaned and prepared to receive the replacement cells.

A small flap of periosteum, the thin layer of tissue covering the bone, is removed from the lower leg bone and sutured over the injured area.

Replacement cells are injected under the periosteum flap, which holds them in place. The cloned cells attach themselves to the lining of the joint and slowly create new cartilage.

Patients are typically on crutches for two to three weeks after the second operation.

Who can benefit:

* People who aren’t suffering from arthritis.

* People under 50 for whom total joint replacement is not usually recommended because the benefits last only 10 to 15 years.

* Patients whose injury is limited to the knee end of the thigh bone.

Source: Genzyme Corp, via the Internet.