Not Recruiting

Trial ID: NCT01609374


This is a prospective, concurrently controlled, multi-center study to evaluate the safety and effectiveness of the Spinal Kinetics M6-C artificial cervical disc compared to anterior cervical discectomy and fusion (ACDF) for the treatment of symptomatic cervical radiculopathy with or without cord compression. Some participating sites will enroll just M6-C patients, while others will enroll just ACDF patients. Patients eligible for study enrollment will present with degenerative cervical radiculopathy requiring surgical intervention, confirmed clinically and radiographically, at one vertebral level from C3 to C7. A total of 243 subjects will be included at up to 20 sites.

Official Title

Prospective, Non-Randomized, Concurrently Controlled, Multi-Center Study to Evaluate the Safety and Effectiveness of the Spinal Kinetics™ M6-C Artificial Cervical Disc Compared to Anterior Cervical Discectomy and Fusion (ACDF) for the Treatment of Symptomatic Cervical Radiculopathy

Stanford Investigator(s)

Lawrence Shuer, MD
Lawrence Shuer, MD

Professor of Neurosurgery

John Ratliff, MD, FACS
John Ratliff, MD, FACS

Professor of Neurosurgery and, by courtesy, of Orthopaedic Surgery


All study subjects must present with degenerative cervical radiculopathy with or without
spinal cord compression, confirmed clinically and radiologically, requiring surgical
intervention at a single vertebral level from C3 to C7.

Inclusion Criteria:

   1. Diagnosis of degenerative cervical radiculopathy with or without spinal cord
   compression requiring surgical treatment at one level from C3 to C7 demonstrated by
   signs and/or symptoms of disc herniation and/or osteophyte formation (e.g. neck and/or
   arm pain, radiculopathy, etc.) and is confirmed by patient history and radiographic
   studies (e.g. MRI, CT, x-rays, etc.)

   2. Inadequate response to conservative medical care over a period of at least 6 weeks

   3. Neck Disability Index score of ≥ 30% (raw score of ≥ 15/50)

   4. Neck or arm pain VAS ≥ 4 on a scale of 0 to 10

   5. Willing and able to comply with the requirements of the protocol including follow-up

   6. Willing and able to sign a study specific informed consent

   7. Skeletally mature and ≥ 18 years old and ≤ 75 years old

Exclusion Criteria:

   1. More than one cervical level requiring surgery

   2. Previous anterior cervical spine surgery

   3. Axial neck pain as the solitary symptom

   4. Previous posterior cervical spine surgery (e.g., posterior element decompression) that
   destabilizes the cervical spine

   5. Advanced cervical anatomical deformity (e.g., ankylosing spondylitis, scoliosis) at
   the operative or adjacent levels

   6. Symptomatic facet arthrosis

   7. Less than 4º of motion in flexion/extension at the index level

   8. Instability as evidenced by subluxation > 3 mm at the index or adjacent levels as
   indicated on flexion/extension x-rays

   9. Advanced degenerative changes (e.g., spondylosis) at the index vertebral level as
   evidenced by bridging osteophytes, central disc height < 4mm and/or < 50% of the
   adjacent normal intervertebral disc, or kyphotic deformity > 11º on neutral x-rays

10. Severe cervical myelopathy (i.e., Nurick's Classification > 2)

11. Active systemic infection or infection at the operative site

12. Co-morbid medical conditions of the spine or upper extremities that may affect the
   cervical spine neurological and/or pain assessment

13. Metabolic bone disease such as osteoporosis that contradicts spinal surgery (for
   females over 50 and males over 55 years old, or if the score on the Osteoporosis
   Self-Assessment Test is < 2, a dual energy x-ray absorptiometry [DEXA scan] of the
   spine is required; if the bone mineral density T-score in the spine is ≤ -2.5 the
   patient must be excluded)

14. History of an osteoporotic fracture of the spine, hip or wrist

15. History of an endocrine or metabolic disorder (e.g., Paget's disease) known to affect
   bone and mineral metabolism

16. Taking medications that may interfere with bony/soft tissue healing including chronic
   steroid use

17. Known allergy to titanium, stainless steels, polyurethane, polyethylene, or ethylene
   oxide residuals

18. Rheumatoid arthritis or other autoimmune disease or a systemic disorder such as HIV,
   active hepatitis B or C or fibromyalgia

19. Insulin-dependent type 1 or type 2 diabetes

20. Medical condition (e.g., unstable cardiac disease, cancer) that may result in patient
   death or have an effect on outcomes prior to study completion

21. Pregnant, or intend to become pregnant, during the course of the study

22. Severe obesity (Body Mass Index > 40)

23. Physical or mental condition (e.g., psychiatric disorder, senile dementia, Alzheimer's
   disease, alcohol or drug addiction) that would interfere with patient self-assessment
   of function, pain or quality of life.

24. Involved in current or pending spinal litigation where permanent disability benefits
   are being sought

25. Incarcerated at the time of study enrollment

26. Current participation in other investigational study that may impact study outcomes


device: Anterior plate system with corticocancellous allograft bone

device: M6-C Artificial Cervical Disc

Not Recruiting

Contact Information

Stanford University
School of Medicine
300 Pasteur Drive
Stanford, CA 94305
Kara Richardson