Fusion of the neck is an ever-changing process. Since the late 1950s, doctors have been able to operate on the neck and perform fusions using an anterior approach. This means the surgeon opens the neck (cervical spine) from the front (throat side) rather than the back of the neck.
Two or more bones of the cervical spine are fused together using pieces of bone shaved from another site. The graft may come from a donor or directly from the patient. Sometimes problems occur with this operation. The problems can be caused by the operation, the graft process, or from the fusion material.
The goal in all methods is to hold the cervical spine in place while saving the natural alignment. This is hard to do when there are problems such as fractures, infection, graft collapse, or graft rejection. For this reason, scientists are trying to find a good substitute to replace the bone graft.
Scientists in Japan are using a man-made ceramic material instead of actual bone. They used dogs in the first study. Two levels of vertebrae were fused together. The first used the bone graft method usually done in humans. The second used the ceramic substitute. In all cases, dogs were the patients.
The fusion material was put in a “fusion cage.” These cages are tiny containers and are commonly made of titanium. The cages are packed with bone graft material and placed between the two vertebral bodies. The fusion cage was invented in the 1980s. The cage is designed to prevent collapse of the bone graft during the natural healing process.
Researchers found that there was no difference in the results using bone graft or a ceramic substitute. The authors conclude that there’s no need to harvest bone from the patient or donor. The cage filled with ceramic fusion material increases the bone strength needed to get the problem vertebrae to fuse together. By using this bone fusion material as a replacement for actual bone grafts, it reduces problems that can come from grafting bone.