At each vertebral level, a disc and a pair of facet joints work together to provide a range of motion.

If there is pain at one or more levels due to disc degeneration, the adjoining segments can be fused together to limit motion and stabilize the segment.

Bone graft is used to fuse the segments; from the patient’s hip (autograft), from a cadaver (allograft), or a synthetic bone graft. Surgical approaches can be from the front (anterior), back (posterior), and/or a combination. A solid fusion occurs when two vertebrae mend or weld together, much like a broken bone healing in a cast.