Cervical spine fusion is a complex operation. The discs are removed from either side of each vertebral body removed. Removal of the vertebral body is called a corpectomy. Ligaments along the spine are cut to give the surgeon access to the bones.
Bone material for the graft is taken from the patient's corpectomy or from a donor bank. The patient's own bone is called an autograft. The fusion rate is usually better when using autograft bone. There are fewer problems with graft rejection and infection with autografts.
Multilevel fusions are less likely to gain a solid fusion because of the number of surfaces that must fuse. The chances for movement are greater if the fusion isn't solid in all areas. And once movement occurs in one area, increased stress on other areas can cause a breakdown of other fused sites.
Studies show that fusion rates are better for multilevel fusions when combining an anterior (from the front) and posterior (from the back) fusion of the spine. The use of expandable cylindrical cages (ECCs) may also improve results of multilevel fusions. These cages can be adjusted to fit the size and shape of the hole left after corpectomy.