Kineflex Artificial Disc System to Treat Degenerative Disc Disease (DDD)

Inclusion Criteria Summary: Be between 18 and 60 years of age Have evidence of degenerative disc disease (DDD) History of back and/or radicular pain which is severe, ongoing and recurrent Minimum 6 month period of prior conservative care Moderate Oswestry Disability Index score Moderate pain score Be likely to return for all follow-up visits Be willing and able to provide Informed Consent for study participation. Exclusion Criteria Summary: Any back or leg pain of unknown origin Foot drop Previous trauma to the study treatment level with compression or bursting Previous retroperitoneal surgery Other spinal surgery at affected level except IDET, laminotomy Previous thoracic or lumbar fusion Documented abnormal abdominal vessel or muscular/fascial pathology or morphology Degenerative spondylolisthesis Ischemic (spondylolytic) spondylolisthesis Spondylitis Documented significant spinal, foraminal or lateral stenosis Severely reduced disc space height Documented presence of free nuclear fragment Extensive facet arthritis or degeneration of the facets at any level noted on MRI, CT or X-ray Scoliosis of the lumbar spine Metabolic bone disease Active systemic infection Hepatitis Active malignancy or history of metastatic malignancy Any terminal or autoimmune disease Any other disease, condition or surgery which might impair healing Recent history of chemical or alcohol dependence Current or extended use of any drug known to interfere with bone or soft tissue healing Known metal allergy Morbid obesity Transitional vertebrae at level to be treated that has not clearly fused Currently a prisoner Currently involved in spinal litigation Currently experiencing an episode of major mental illness Pregnancy at time of enrollment, since this would contraindicate abdominal surgery Participation in another drug, diologic or medical trial within 30 days of study surgery Lives more than 300 miles from a study center or participation in any other investigational drug, biologic or medical device study.