New Study Finds that Bone Grafts Are Likely to Resorb, Especially in Younger Patients

A new study suggests that bone-grafting appears to have limited value in treating fibrous dysplasia and McCune-Albright syndrome. The study was funded in part by a grant from the Fibrous Dysplasia Foundation.

The study, conducted at the National Institutes of Health, followed patients with polyostotic fibrous dysplasia over an average of 20 years. The study looked at many different types of bone graft procedures including autograft procedures (grafts using patient’s own bone), allograft procedures (grafts from another person, often called cadaver bone), procedures that used a combination of autograft and allograft bone, grafts that served a structural purpose (such as supporting rods), and grafts that served no structural purposes.

Researchers found that 71% of the bone grafts were fully resorbed over time, meaning that the healthy transplant bone reverted back into fibrous dysplasia bone lesions. Only 25% of the grafts survived and were incorporated into the bone long-term. 4% grafts were partially resorbed. Of the bone grafts that were resorbed, the grafts lasted an average of 10 years.

Researchers believe that age at the time of surgery may explain why some patients experienced resorption, and others did not. On average, patients who experience resorption were about 10 years old at the time of surgery, and the patients with bone graft survival were older, or about 21 years old.

When asked about this study, leading orthopedic surgeon Robert Stanton said, “I am grateful that Dr. Collins and his colleagues have definitively put to rest the notion that bone grafting in children with polyostotic fibrous dysplasia will be of any benefit in managing the deformities of long bones.  This is consistent with the advice that I and my orthopedic colleagues have been espousing at our annual MAGIC Foundation meetings and at the Fibrous Dysplasia Foundation meetings for years.  By appearing in the journal that has the most widespread readership among orthopedic surgeons, one can hope that the word will get out to those surgeons who only rarely treat children with FD.”

Age was the only factor that seemed to predict which bone grafts resorbed and which bone grafts survived. Researchers did not find evidence of an advantage of using one type of bone graft material over another and did not find that bisphosphonate-use predicted bone graft success.

There may be some select situations where bone grafts are still useful. For example, Dr. Stanton noted,  “I still use bone grafts for the small bones of the hands and feet if those bones are experiencing multiple fractures. I also will occasionally use bone graft to initially fill an aneurysmal bone cyst in fibrous dysplasia, but expect that the graft will be replaced with fibrous dysplasia in a few weeks, which, of course, is stronger than a blood-filled cyst.”

For the full article, “Bone-Grafting in Polyostotic Fibrous Dysplasia,” click here.