Kineflex/C Artificial Disc System to Treat Cervical Degenerative Disc Disease (DDD)

• Improvement in Neck Disability Index (NDI) Score at 24 months compared with baseline [ Time Frame: 24 months ] [ Designated as safety issue: No ]
• No major device related adverse events [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]

• Improvement in NDI Score at 24 months compared with baseline
• No major device related adverse events.

• Clinically significant improvement in one or more radicular symptoms at 24 months compared to baseline [ Time Frame: 24 months ] [ Designated as safety issue: No ]
• Time to recovery [ Time Frame: 24 months ] [ Designated as safety issue: No ]
• Disc height at 24 months compared to baseline [ Time Frame: 24 months ] [ Designated as safety issue: No ]
• Adjacent level deterioration at 24 months compared to baseline [ Time Frame: 24 months ] [ Designated as safety issue: No ]
• Progressive facet disease at 24 months compared to baseline [ Time Frame: 24months ] [ Designated as safety issue: No ]
• Displacement or migration of the device [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
• Odom's Criteria [ Time Frame: 24 months ] [ Designated as safety issue: No ]

• Clinically significant improvement in one or more radicular symptoms at 24 months compared to baseline
• Time to recovery
• Disc height at 24 months compared to baseline
• Adjacent level deterioration at 24 months compared to baseline
• Progressive facet disease at 24 months compared to baseline
• Displacement or migration of the device
• Odom’s Criteria

The purpose of this study is to show that the Kineflex/C Spinal System is no worse than conventional Anterior Cervical Diskectomy with Fusion (ACDF) in patients with single level degenerative disc disease at any cervical level from C3 to C7.

The Kineflex/C disc is a 3-piece modular design consisting of two cobalt chrome molybdenum (CCM) end-plates and a fully articulating CCM core. The system is available in two foot print sizes.

• Device: Artificial disk
  Implant
• Device: Artificial disc
  Implant

• Experimental: Kineflex-C
  Interventions:

  • Device: Artificial disk
  • Device: Artificial disc
• Active Comparator: ACDF
  Interventions:

  • Device: Artificial disk
  • Device: Artificial disc

Inclusion Criteria:

• have symptoms of cervical degenerative disc disease (DDD) at only one cervical level from C3 to C7, disc herniation on CT or MRI;
• have radiculopathy symptoms in neck, one or both shoulders, and/or one or both arms;
• have at least six months of prior conservative treatment (e.g., physical therapy and/or use of anti-inflammatory medications and muscle relaxants at the manufacturer's recommended therapeutic dose), the presence of progressive symptoms (e.g., increasing numbness or tingling), or signs of nerve root compression;
• have moderate disability neck disability index (NDI) score; AND
• be likely to return for all follow-up visits and be willing and able to provide informed consent for study participation

Exclusion Criteria:

• marked cervical instability;
• non discogenic neck pain or non discogenic source of symptoms;
• radiographic confirmation of severe facet disease or facet degeneration;
• bridging osteophytes;
• prior surgery at the level to be treated;
• prior fusion at any cervical level;
• more than one neck surgery via anterior approach;
• previous trauma to the C3-C7 levels resulting in compression or bursting;
• documented presence of free nuclear fragment at any cervical level;
• severe myelopathy;
• any paralysis;
• history of chemical or alcohol dependence;
• active systemic infection;
• infection at the site of surgery;
• prior disc space infection or osteomyelitis in the cervical spine;
• any terminal, systemic or autoimmune disease;
• metabolic bone disease (e.g., osteoporosis, gout, osteomalacia, Paget's disease);
• any disease, condition or surgery which might impair healing;
• known metal allergy;
• arachnoiditis;
• currently experiencing an episode of major mental illness;
• pregnancy at time of enrollment, or planning to become pregnant, since this would contraindicate surgery;
• morbid obesity; use of spinal stimulator at any cervical level prior to surgery;
• currently a prisoner;
• currently involved in spinal litigation which may influence the subjects reporting of symptoms; OR
• lives more than 300 miles from study center or participation in any other investigational drug, biologic, or medical device study within the last 30 days prior to study surgery