Twenty-five years ago surgeons tried a procedure called abrasion arthroplasty to stimulate cartilage repair in the knee. The idea was to cause bleeding to encourage healing and cause cartilage to grow again. The practice was stopped because too many patients reported increased pain after the operation.

At least one group of surgeons in Germany didn't put the practice aside. They realized the problem was drilling or cutting the bone (instead of shaving or abrading) and going too deep. Just the right amount of stress on the cartilage is needed to generate cartilage regrowth. Removing too much bone weakens it and makes weight-bearing more painful.

The results of several long-term studies of 100s of patients who received abrasion arthroplasty are now available. It turns out the operation actually helped many patients avoid a total knee replacement. Repair growth and function got better and better months and even years after resurfacing the bone.

Results were also reported for another study of patients receiving autologous chondrocyte implanted (ACI)-covered flaps to repair cartilage defects. Healthy cartilage cells from each patient were removed and grown in a laboratory then reimplanted in the patient. Twenty-five years of data shows that 85 percent of the grafts lasted 10 or more years.

The same type of data was collected for osteochondral allografts (OCA). In this operation the patient receives cartilage with a bone plug from a donor. Holes are drilled and the OCA is inserted in the damaged joint. The allograft restored bone stock making conversion to a total knee joint easier years later.

As a result of these studies, orthopedic surgeons are taking a second look at cartilage repair techniques tried and abandoned years ago. Tweaking the process may bring about new ways to salvage damaged joints without replacing the joint.

Reference:

Gina Brockenbrough. Surgeons Revisit Original Cartilage Repair Techniques. In Orthopedics Today. March 2006. VO. 26. No. 3. Pp. 12-19.'