The purpose of this investigation is to establish the safety and effectiveness of the LDR Spine Mobi-C® Cervical Disc Prosthesis which is an anterior cervical interbody mechanical device. The primary objective of the study is to evaluate the overall success rate of the investigational device as compared to the control in the treatment of patients with symptomatic DDD with radiculopathy or myeloradiculopathy at one or two adjacent levels. Patients should be without prior cervical fusion between C3 and C7 and unresponsive to non-operative conservative treatment for six weeks after symptom onset or have the presence of progressive symptoms or signs of nerve/spinal cord compression despite continued non-operative conservative treatment.

Objectives of the Investigation

The purpose of this investigation is to establish the safety and effectiveness of the LDR Spine Mobi-C® Cervical Disc Prosthesis which is an anterior cervical interbody mechanical device. The primary objective of the study is to evaluate the overall success rate of the investigational device as compared to the control in the treatment of patients with symptomatic DDD with radiculopathy or myeloradiculopathy at one or two adjacent levels. Patients should be without prior cervical fusion between C3 and C7 and unresponsive to non-operative conservative treatment for six weeks after symptom onset or have the presence of progressive symptoms or signs of nerve/spinal cord compression despite continued non-operative conservative treatment.

Study Design Rationale

The study is a prospective, randomized, multi-center, concurrently controlled investigation, in which the study device will be compared to the control treatment consisting of conventional anterior cervical discectomy and fusion (ACDF) in accordance with the Smith-Robinson procedure. Patients will be followed for two years postsurgery (primary endpoint) and at 3, 4, 5, and 7 years thereafter.

Duration of the Investigation

Patients will be followed post-operatively at 6 weeks, and 3-, 6-, 12-, 18-, and 24-months. After 24 months, patients will continue to be followed at 3,4, 5 and 7 years.

Design Techniques to Avoid Bias

To eliminate selection bias, investigational and control comparison groups will be assigned at random.

Institutional Review Board

No clinical studies will begin without documented approval of the clinical investigation by the Institutional Review Board (IRB) affiliated with the study center.

Inclusion Criteria:

1. Age 18-69 years.

2. Diagnosis of radiculopathy or myeloradiculopathy of the cervical spine, with pain, paresthesias or paralysis in a specific nerve root distribution C3 through C7, including at least one of the following:

   • Neck and/or arm pain (at least 30mm on the 100mm VAS scale).
   • Decreased muscle strength of at least one level on the clinical evaluation 0 to 5 scale.
   • Abnormal sensation including hyperesthesia or hypoesthesia; and/or
   • Abnormal reflexes

3. Symptomatic at one or two adjacent levels from C3 to C7;

4. Radiographically determined pathology at one or two adjacent level(s) to be treated correlating to primary symptoms including at least one of the following:

   • Decreased disc height on radiography, CT, or MRI in comparison to a normal adjacent disc.
   • Degenerative spondylosis on CT or MRI.
   • Disc herniation on CT or MRI;

5. Neck Disability Index Score of ≥15/50 or ≥30%;

6. Unresponsive to non-operative, conservative treatment (rest, heat, electrotherapy, physical therapy, chiropractic care and/or 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.

Note: Not a complete listing

Exclusion Criteria:

1. Reported to have an active systemic infection or infection at the operative site;
2. Reported to have a history of or anticipated treatment for active systemic infection, including HIV or Hepatitis C;
3. More than one immobile vertebral level between C1 to C7 from any cause including but not limited to congenital abnormalities and osteoarthritic "spontaneous" fusions;
4. Previous trauma to the C3 to C7 levels resulting in significant bony or disco-ligamentous cervical spine injury;
5. Reported to have had any prior spine surgery at the operative level;
6. Reported to have had prior cervical fusion procedure at any level;
7. Axial neck pain in the absence of other symptoms of radiculopathy or myeloradiculopathy justifying the need for surgical intervention;
8. Disc height less than 3mm as measured from the center of the disc in a neutral position and disc height less than 20% of the anterior-posterior width of the inferior vertebral body;
9. Radiographic confirmation of severe facet joint disease or degeneration;

Note: Not a complete listing