I have a chance to be part of a study using a dissolving plate to fuse my neck. I'm wondering what you think about these.

Bioabsorbable plates are fairly new to the spinal fusion scene. For a long time now, surgeons have used an approach called the anterior cervical discectomy and fusion (ACDF). Anterior refers to the location of the incision and the way surgeon enters the spine (front of the neck). Anterior fusion is performed through the front of the spine to avoid the spinal cord and spinal nerves. Cervical refers to the neck and discectomy is the removal of the disc from between two vertebrae. Most surgeons use bone graft material to fill in the space left by removal of the disc and a metal plate to hold the spine in place while the bone graft material fills in.

Fusion rates have improved greatly with this surgical technique. But even as successful as this approach has been, there can still be problems. Sometimes the screws back out and/or the plate shifts its position. Because the plate is along the front of the spine, swallowing can be impaired. Stiffness is the desired outcome of fusion in order to provide stability. But too much stiffness is a potential problem when using a metal plate system. And X-rays can't penetrate the metal plate, so it's difficult to assess the fusion site.

That's why plates that eventually break down and become absorbed into the fusion have been developed. But even with all of the technical advances with this procedure, there can still be problems. Studies show that while the fusion rate is good, the rate of subsidence is still high for the bone graft used in the procedure. Subsidence means the extra bone used to fill in sinks down into the vertebra, leaving it less stable than a solid fusion.

Major complications (e.g., infection, bleeding) are about the same as with the standard metal instrumentation. Some patients still reported neck and arm pain. Loss of function or failure to resume normal everyday activities accounted for a 41 per cent rating of poor-to-good (rather than excellent). Slightly more than half (59 per cent) of the patients had excellent results.

The result of research suggests that bioabsorbable plates stabilize the spine better than having no plate but there are enough problems that further study and improvements in this technique are required before it can be recommended instead of metal instrumentation for ACDF procedures. Long-term study is also needed to see how patients (and the graft site) fare years down the road. Unlike permanent plates, with the dissolving kind, there won't be any plate-related complications years later as there have been with metal instrumentation.