With fusion, there is no motion left at the level operated on. This can translate the force of the load through the spine to the next level up. There have been many concerns about disc degeneration at the adjacent level.
ADR is a fairly new operation. The implants are being studied and improved upon. Surgeons are still gaining practice and improving in the skills needed to do this procedure. But studies so far show four distinct advantages of ADR over fusion.
First, there is less soft tissue damage and a decreased risk of dysphagia (difficulty swallowing) with ADR. Fewer muscles have to be cut and moved out of the way. Second, the load and strain placed on the next-level of vertebra is less with ADR. Since motion is preserved, the natural forces are shared by all segments.
Third, large studies have shown that there's a higher reoperation rate with cervical fusion. And there's also more adjacent level disease that occurs after fusion.
Finally, when more than one level is fused, there is a corresponding increase in problems and poor results. The opposite may be true with multiple ADRs. At least one study (the first) showed that multiple level ADRs had better overall results compared to single-level implants.
Once you complete your course of rehab, your surgeon will be better able to advise you as to your options. He or she will review the pros and cons of each treatment choice to better help you make a final decision.