Joint pain is a common problem facing patients and their physicians. Many of us have experienced a sprained ankle or knee. Imagine having that pain all the time and you’ll understand what people with arthritis or other more permanent joint problems experience. The underlying cause of many such joint problems is loss of cartilage, the smooth, white substance that coats the ends of bones. The drumstick on your Thanksgiving turkey has cartilage on the end of it and so do all of the bones in your joints. When that cartilage begins to wear off, it cannot heal or be replaced naturally because cartilage has no blood supply. Surgeons can sometimes remove or trim off loose pieces of cartilage and that helps a Unfortunately, there has been no good way to replace or repair cartilage once it is gone. That is why people with certain cartilage problems have to live with the pain until it is bad enough to justify knee or hip replacement surgery.

Recently, however, some techniques have evolved that can help some people; they are currently being used for the knee joint. The general idea is to fill in the hole in the cartilage with new cartilage. The old technique relied on scraping out the defect, making holes in the bone to let new blood vessels come in, and letting scar tissue grow in to fill the defect. Unfortunately, scar tissue does not hold up to daily wear and tear like real cartilage.

Two new techniques are now available at Kent & Queen Anne’s Hospital. Using one technique that was recently approved by the FDA, a piece of cartilage from the patient is sent to a lab in Boston. Genzyme Tissue Repair, the only company currently doing this commercially, then grows several million new cartilage cells under controlled conditions. These are cultures of the patient’s own cells which are programmed to make more cartilage. In a few weeks a vial of fluid containing those cells is shipped to the Hospital and the cells are reimplanted during an outpatient surgical procedure.

In most patients these cells fill in the defect with what looks and acts like normal cartilage. It can take several months until the process is complete, and the process only works on relatively small defects in certain regions of the knee.

A second technique is also being used. This process is uses plugs of bone and cartilage to fill the defect much in the same way plugs of hair are moved to cover a bald spot. Those plugs have to be removed from another part of the same knee. For small defects, removing those plugs from elsewhere won’t do much harm, and filling in the weight-bearing area will help the patient.

Plugs can only fill small defects because you can only remove so many without possibly causing more trouble. However, the bone plug technique may be accomplished for $5,000-$6,000 whereas removing, growing and reimplanting cartilage cells may cost nearly $30,000. As a result, many insurance companies may not cover the more expensive procedure.

These new options offer some hope for a limited number of patients although patients with widespread cartilage loss still generally face joint replacement surgery.