Empty Cage Implant for Neck Fusion
Disc herniation in the neck can be treated with surgery. There are different ways to approach this problem. Doctors generally agree that the disc must be taken out, but then what? Should the disc be replaced by bone graft or artificial bone?
Just removing the disc and leaving the neck as it is can cause bone collapse and other problems. Bone grafts to help fuse the spine are risky. Besides infection in the neck, there can be pain and infection at the site where the bone graft was taken from (usually the pelvic bone).
In the last few years, doctors have worked to find some answers to these problems. New materials to replace the disc are the center of today's research on neck surgery. These new materials are called interbody implants or "cages." The cage comes in various shapes and heights. It may be made of metal, graphite, or bone. Most cages are designed so they can be packed with bone chips or a suitable bone graft substitute.
In this study, doctors in Geneva, Switzerland, used a new carbon material and left the cages empty. This method is safe and prevents problems with bone grafting. The researchers found that bone grows through and around the cage. The bone isn't as dense as bone from a graft site, and there was some settling of the cage into the bone above.
Use of implants or cages for neck fusion after disc removal is likely here to stay. The authors of this study are already planning the next step. They plan to increase the size and support of the cages and compare it to other methods used for this operation.
Michael Payer, MD, et al. Implantation of an Empty Carbon Fiber Composite Frame Cage After Single-Level Anterior Cervical Discectomy in the Treatment of Cervical Disc Herniation: Preliminary Results. In Journal of Neurosurgery: Spine. March 2003. Vol. 98. No. 3. Pp. 143-148.