The Synergy Disc for the Treatment of 2 Level Cervical Degenerative Disc Disease Compared With Cervical Fusion Surgery

This is a research study comparing two ways of treating neck problems caused by degenerative disc disease (wear-and-tear damage to the discs that cushion the bones in the neck). The study is comparing: The Synergy Disc - an artificial disc device being studied in this trial, and Standard surgery (ACDF) - a widely used procedure called anterior cervical discectomy and fusion, which is the accepted current treatment. Up to 200 people will receive the Synergy Disc as part of this study. Their results will be compared to results from people who had the standard ACDF surgery in the past, rather than assigning some people to get ACDF during this study (this is called a "historical control"). The study takes place at multiple medical centers. Who this study is for: People who are fully grown (skeletally mature) and have damage in two neighboring discs in the neck (located somewhere between the C3 and C7 vertebrae). To qualify, a person's symptoms must include: Arm pain and/or nerve-related weakness or numbness (radiculopathy) that hasn't improved, and Neck pain or signs of spinal cord compression (myelopathy) These symptoms must be caused by problems in the two affected disc levels, and must not have gotten better with non-surgical treatment (such as physical therapy, medication, or injections). What the study will measure: Whether the Synergy Disc is as safe and effective as standard ACDF surgery for people who need surgery to relieve pressure on the nerves or spinal cord at two neighboring disc levels in the neck.