2-level Cervical Disc Replacement Comparing Prodisc C SK & Vivo to Mobi-C

Inclusion Criteria: 1. Age ≥18 and ≤69 years. 2. Diagnosis of radiculopathy or myelopathy with radiculopathy of the cervical spine, with pain, paresthesias or paralysis in a specific nerve root distribution C3 through C7, including at least one of the following: 3. Symptomatic cervical disc disease (SCDD) at two contiguous levels from C3 to C7. 4. Radiographically determined pathology at the level to be treated correlating to primary symptoms. 5. Unresponsive to non-operative, conservative treatment (rest, heat, electrotherapy, physical therapy, chiropractic care and/or analgesics) Exclusion Criteria: 1. Have more than one immobile vertebral level between C1 to C7 from any cause including but not limited to congenital abnormalities and osteoarthritic "spontaneous" fusions. 2. Have previous trauma to the C3 to C7 levels resulting in significant bony or disco-ligamentous cervical spine injury. 3. Have had a prior cervical TDR or fusion procedure at any level. 4. Have osteoporosis or is at increased risk of osteoporosis 5. Have active malignancy that included a history of any invasive malignancy (except non-melanoma skin cancer), unless the subject had been treated with curative intent and there had been no clinical signs or symptoms of the malignancy for at least 5 years. 6. Have known allergies to cobalt, chromium, molybdenum, titanium, nickel or polyethylene. 7. Have rheumatoid arthritis, lupus, or other autoimmune disease that affect the musculoskeletal system. 8. Have concomitant conditions requiring daily, high-dose oral and/or inhaled steroids. 9. Have a Body Mass Index (BMI) \> 40 kg/m2. 10. Taking medications known to potentially interfere with bone/soft tissue healing (e.g., high-dose oral and/or inhaled steroids, immunosuppressant medication, chemotherapeutic agents). 11. Have a current history of heavy smoking (more than one pack of cigarettes per day).