Children Being Surgically Treated with Off-Label Spine Fusion Protein Treatments

Emerging data reveals that thousands of children have been treated with bone growth products during surgery and that these products are being used off-label.

Some 9.2% of spinal fusion surgeries preformed on children involved the off-label use of bone morphogenetic protein (BMP), a costly and unapproved use, MedPage Today noted. The study authors cautioned that complications reported in adults treated with BMPs, such as Medtronic’s Infuse®, “would not be expected during hospitalization.”

Data from more than 8,000 pediatric spinal fusion procedures was reviewed and revealed that the median cost for spinal fusions in which BMP was used was $47,136 versus $43,126 for non-BMP procedures, wrote Emily Dodwell, MD, of the Hospital for Special Surgery in New York, in a research letter published in the October 10 issue of the Journal of the American Medical Association, said MedPage Today. The team analyzed a sample of 4,121 U.S. hospitals involved in the “Kids’ Inpatient Database.”

In non-pediatric use, BMPs, including Medtronic’s Infuse®, have been linked to some significant complications such as “wound dehiscence, spinal stenosis, and respiratory stenosis,” according to the study. We’ve also noted that Infuse® has been associated with adverse health effects such as infections, pain, cysts, male sterility, increased cancer risks, bone dissolution, and worsening back and leg pain.

While Dodwell said that the analysis was limited by a lack of longitudinal data, she noted that BMP use in children should be stopped “until it has been shown to be safe and beneficial…. We don’t know if it is necessary or if it will present some deleterious affects,” she added, according to MedPage Today. “BMP is a powerful molecular growth (agent), and its use in kids is concerning,” noted Sohail Mirza, MD, a professor of orthopedics at the Dartmouth Medical School, who was not involved in the study.

As we’ve explained, Medtronic Infuse®—approved by the U.S. Food & Drug Administration (FDA) in 2002 to stimulate spine growth in patients suffering from lower spinal degenerative disease—is a synthetic form of recombinant human Bone Morphogenetic Protein (rhBMP-2) approved for use in one type of spinal surgery and some dental procedures. The product is used, for the most part, in off-label procedures.

The product’s approval was based on research funded by Medtronic, noted MedPage Today. Meanwhile, Medtronic has been at the center of a conflict-of-interest scandal after a government report revealed that none of some 13 Medtronic-funded clinical trials reported Infuse® side effects, despite that data provided to the FDA revealed that at least half of all patients treated with Infuse® suffered complications. The U.S. Senate Finance Committee inquiry initiated in June 2011 probed surgeons paid by Medtronic who had not reported these Infuse®-related complications.

“The use of BMP in children is worrisome,” said Richard Deyo, MD, a physician and professor with Oregon Health & Science University, wrote MedPage Today. “I’d be concerned that some of the longer-term complications occasionally seen in adults—such as excessive bone growth—could occur in children. The evidence of possibly increased cancer risk with high-dose use in adults would also raise concerns in children.” Deyo, an expert on spine surgery, was not involved in the research.

Some experts worry about the growth factors being administered into the growing bodies of children, said MedPage Today, which noted that growth factors used in products, such as Infuse®, are naturally-occurring proteins in the body that stimulate cell growth. “If you want to use this in thousands and thousands of children, you need to do basic safety research,” said Eugene Carragee, MD, a professor of orthopedic surgery at Stanford University in Palo Alto, California, who has researched BMP. “They are a vulnerable population,” Carragee added, said MedPage Today.