Evaluation of Safety and Effectiveness of Primary Hybrid Construct of Mobi-C and ACDF in the Treatment of Two-level Symptomatic Degenerative Disc Disease in the Cervical Spine.

Inclusion criteria

• 1. Age 22 - 69 years. 2. Have symptoms of cervical degenerative disc disease (DDD) at two levels from C3 to T1 defined as intractable radiculopathy (arm pain and /or a neurological deficit) with or without neck pain or myelopathy due to a two-level abnormality localized to the level of the disc space.

• Radiographic evidence of at least one of the following:

a. Spondylosis (defined by the presence of osteophytes or dark disc) on CT or MRI; or b. Disc height decreased by ≥1 mm when compared to adjacent levels on radiographic film, CT, or MRI; or c. Disc herniation on CT or MRI. Appropriate treatment for using an anterior surgical approach, including having no prior surgery at the operative levels and no prior cervical fusion or arthroplasty procedure.

• Neck Disability Index Score of ≥15/50 or ≥30%. 5. Unresponsive to non-operative, conservative treatment (rest, heat, electrotherapy, physical therapy, chiropractic care and analgesics) for:
• Approximately six weeks from radiculopathy or myeloradiculopathy symptom onset; or
• Have the presence of progressive symptoms or signs of nerve root/spinal cord compression despite continued non-operative conservative treatment.

• Able and willing to comply with the Protocol, including ability to read and complete required forms and willing and able to adhere to the scheduled follow-up visits* and requirements of the Protocol 7. Written informed consent provided by subject or subject's legally authorized representative.

*Note that patients who live significant distances away from a treatment center are statistically likely to be present for treatment but are not likely to return for all follow-up visits. For this reason, patients who live over 150 miles from a treatment center are not eligible for treatment in this clinical study without prior approval from the study Sponsor.

Exclusion criteria

• 1. Symptomatic DDD or significant cervical spondylosis at more than two levels 2. Reported to have an active systemic infection or infection at the operative site 3. Previous trauma resulting in significant bony or disco-ligamentous cervical spine injury 4. More than one immobile vertebral level between C1 to C7 from any cause including but not limited to congenital abnormalities and osteoarthritic "spontaneous" fusions 5. Reported to have had any prior fusion or CDA surgery in the cervical spine 6. Axial neck pain only (no radicular or myelopathy symptoms) 7. Disc height ≤25% of the anterior-posterior width of the inferior vertebral body 8. Severe facet joint disease or degeneration; or evidence of symptomatic moderate to severe facet joint degeneration or disease where the investigator feels this is a major contributor to the patient's pain as diagnosed by injection and imaging 9. Marked cervical instability on resting lateral or flexion/extension radiographs demonstrated by:

• Translation greater than 3.5mm, and/or
• Greater than 11° angular difference to that of either adjacent level 10. Segmental angulation of greater than 11° at treatment or adjacent levels 11. Metabolic bone disease (e.g., osteoporosis/osteopenia, gout, osteomalacia, Paget's disease) 12. Reported to have osteoporosis (T-SCORE greater than -1.0). All patients 50 years and older, post-menstrual, and females with hysterectomies will undergo a DEXA scan or hologic sahara as part of the study enrollment procedures.
• For patients less than 50 years of age, the Simple Calculated Osteoporosis Risk Estimation (SCORE) questionnaire will be used to screen patients for osteoporosis. Patients whose screening suggests risk will undergo a DEXA scan.
• Patients will be excluded if the DEXA scan results indicate a T-SCORE worse than -1.0 13. Any disease, condition or surgery which might impair healing, such as: Diabetes mellitus requiring daily insulin management 14. Active malignancy 15. Known sensitivity or allergies to any of the materials used with any of devices in study (e.g., cobalt chromium, titanium, polyethylene, PEEK) 16. Reported pregnancy or nursing at time of enrollment 17. Reported to have rheumatoid arthritis, lupus, or other autoimmune disease that affect the musculoskeletal system 18. Congenital bony and/or spinal cord abnormalities that affect spinal stability 19. Reported to have diseases or conditions that would preclude accurate clinical evaluation (e.g. neuromuscular disorders) 20. Reported concomitant conditions requiring steroid treatment 21. Reported to be taking medications known to potentially interfere with bone/soft tissue healing, e.g., long term use of corticosteroids (this does not include inhalation medications for asthma) 22. Reported to have a current history of heavy smoking (no less than one pack of cigarettes per day) 23. Recent history (within previous six months) of chemical or alcohol dependence 24. Morbid obesity, as defined by NIH Clinical Guidelines Body Mass Index (BMI > 35) 25. Participation in any other investigational drug, biologic, or medical device study within the last 30 days prior to study surgery 26. Currently involved in spinal litigation or receiving Worker's Compensation related to neck or back pain which may influence the subjects reporting of symptoms 27. Reported to have mental illness or belongs to a vulnerable population as determined by the investigator (e.g., prisoner or developmentally disabled) that would compromise ability to provide informed consent or compliance with follow-up requirements 28. Reported to have an uncontrolled seizure disorder