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

Exclusion Criteria

• •Subjects who meet any of the following criteria will be excluded from participation in this study:
• •1. Has a cervical spinal condition other than symptomatic cervical DDD requiring surgical treatment at the involved levels;
• •2. Has documented or diagnosed cervical instability relative to adjacent segments at either level, defined by dynamic (flexion/extension) radiographs showing:
• •1. Sagittal plane translation \> 3.5 mm, or
• •2. Sagittal plane angulation \> 20°;
• •3. Prior attempted or completed cervical spine surgery, except (1) laminoforaminotomy (greater than 6 months prior to scheduled surgical treatment), which includes removal of disc material necessary to perform a nerve root decompression, with less than one-third facetectomy at any level, or (2) a successful single-level anterior cervical fusion (greater than 6 months prior to scheduled surgical treatment);
• •4. Has severe pathology of the facet joints of the involved vertebral bodies;
• •5. Axial neck pain only (no radicular or myelopathy symptoms);
• •6. Has been previously diagnosed with osteomalacia;
• •7. Osteoporosis: A screening questionnaire for osteoporosis, SCORE (Simple Calculated Osteoporosis Risk Estimation) for females or MORES for males (Male Osteoporosis Risk Estimation Score), will be used to screen patients to determine those patients who require a DXA of the hip, a bone mineral density measurement. A SCORE or MORES ≥6 requires a DXA. If DXA is required, exclusion will be defined as a DXA bone density measured T score ≤ -2.5 (The World Health Organization definition of osteoporosis). DXA scans within the last 6 months prior to surgical treatment may be used;
• •8. Has presence of spinal metastases;
• •9. Has overt or active bacterial infection, either local or systemic;
• •10. Has insulin-dependent diabetes;
• •11. Has chronic or acute renal failure or prior history of renal disease;
• •12. Known titanium or UHMWPE allergy;
• •13. Is mentally incompetent (if questionable, obtain psychiatric consult);
• •14. Is a prisoner;
• •15. Is pregnant ;
• •16. Is currently an alcohol and/or drug abuser or currently undergoing treatment for alcohol and/or drug abuse;
• •17. Is involved with current or pending litigation regarding a spinal condition;
• •18. Has received drugs that may interfere with bone metabolism within two weeks prior to the planned date of spinal surgery (e.g., steroids or methotrexate), excluding routine perioperative anti-inflammatory drugs;
• •19. Has a history of an endocrine or metabolic disorder known to affect osteogenesis (e.g., Paget's Disease, renal osteodystrophy, Ehlers-Danlos Syndrome, or osteogenesis imperfecta);
• •20. Has a condition that requires postoperative medications that interfere with the stability of the implant, such as steroids. This does not include low-dose aspirin for prophylactic anticoagulation and routine perioperative anti-inflammatory drugs;
• •21. Has received treatment with an investigational therapy within 28 days prior to implantation surgery or such treatment is planned during the 16 weeks following implantation