Since 2002 surgeons have had a special tool in their box of techniques for spinal fusion. And that is a substitute for bone graft called bone morphogenetic protein or BMP. Although more expensive, this product has two major advantages over using the patients’ own bone: 1) patients no longer suffer pain and discomfort at the pelvic crest where donor bone was taken from and 2) patients with poor bone growth due to diabetes or tobacco use can have a spinal fusion when necessary.
But as you have heard, there are some serious complications and post-operative problems being reported. So it’s time to take a second look at the safety of this bone substitute product. BMPs were first discovered in 1965 with more than 20 types now being studied. Only one (BMP-2) has been approved for use by the Food and Drug Administration (FDA) in spinal fusion surgeries.
When used as it was approved and intended, BMP stimulates safe and effective bone growth to aid in the fusion process. And that primary use for which it was intended is only anterior lumbar (low back) interbody fusion. Troubles begin when this product is used off-label such as for cervical (neck) fusion, especially anterior (from the front of the spine) procedures and posterior (from the back) lumbar fusion.
Massive soft tissue swelling, extra bone formation, seromas (fluid-filled pockets), and even cancer have been reported as emerging concerns with BMP-use. BMP receptors have been found on some (but not all) types of cancer cells. Since BMP stimulates bone growth, there is concern that it could actually promote the formation of cancer cells or speed up cancer metastases (spread).
The number of patients who have developed cancer after receiving BMP in spinal fusions is small. But the rate of increase compared to fusion patients without BMP is significant. Therefore, until further studies are done, the current recommendation is to only use patient bone graft material for individuals who have had a history of cancer or who have active cancer at the time of the intended spinal fusion.
Some experts suggest that the link between BMP and cancer is only when high-doses of BMP are used — much higher than the dose applied during a spinal fusion. If you have not experienced any problems in the first two years, a little watchful waiting may be advised since problems have been reported up to five years later. Talk with your surgeon about your situation. Ask him or her about your own risk and what to watch out for.