A Clinical Trial Evaluating a Total Disc Replacement in Patients With Cervical Disc Disease

Inclusion criteria

• ✓. Age: 18-60 years of age (inclusive and skeletally mature);
• ✓. A diagnosis of symptomatic cervical disc disease, defined as image-confirmed pathology: herniated disc, spondylosis, and/or loss of disc height. Spondylosis is defined as image-confirmed disc desiccation, loss of disc height, bridging osteophytes, and/or uncovertebral arthrosis. Loss of disc height is specified as a measurement of at least 25 degrees less than an adjacent nonsymptomatic level, but with a minimum of 1mm height remaining;
• ✓. Functional neurological deficit (i.e., exhibits at least one sign associated with cervical level to be treated, including abnormal reflex, decreased motor strength, abnormal dermatome sensitivity, or pain in a dermatomal distribution);
• ✓. Symptomatic level is C3-4, C4-5, C5-6 or C6-7 (one level);
• ✓. Preoperative Neck Disability Index (NDI) greater than 30 points (considered moderate disability; Vernon 1991);
• ✓. Unresponsive to conservative treatment for more than 6 weeks, and/or exhibits progressive symptoms and/or signs of nerve root and/or spinal cord compression in the face of conservative treatment;
• ✓. Not pregnant, nor interested in becoming pregnant within the follow-up period of the study;
• ✓. Willing and able to comply with the requirements defined in the protocol for the duration of the study;