Cervical Disc Arthroplasty David Urquia, MD

Also known as "Total Disc Arthroplasty (TDA), or generically to patients as "cervical disc replacement" or “cervical disc arthroplasty (CDA), the concept creates an alternative to anterior fusion in the cervical spine.

Although anterior cervical discectomy and fusion (ACDF) has been a universally successful procedure for the treatment of radiculopathy and stenosis, and truly represents the “gold standard” for cervical spinal surgery, we are always looking for something better. The main concern with spinal fusion has always the negative effect of loss of spinal motion, and the potential for “adjacent-level disease.” Motion-sparing operations in the spine are relatively new concepts. Lumbar “disc replacements” were tried first but have not seen widespread use and are rarely performed except in a few centers.

Cervical Disc Arthroplasty (replacement) evolved in Europe for many years, and now there are second- and third- generation designs on the market in the U.S. and a half dozen or so now have FDA approval, at least for single- level use. Fortunately, we have good data out four years or more on some of these implants that shows efficacy as good or better than ACDF fusions in comparable cases.

The indications for cervical TDA are basically the same as we use for ACDF – a neurological diagnosis of radiculopathy and/or spinal stenosis. Patient selection criteria are more strict for TDA in that patients must have only one- or two-level disease, minimal arthritis, no spinal instability or misalignment, and good quality bone density.

Age is not a restriction by itself, although patients older than 50 are less common for TDA because of arthritis. However, finding private insurance third-party payers willing to cover the cost of the implant in reality has been the main obstruction to more common use of TDA, as the cost of the TDA implant is greater than our current plate/screw/bone graft combination. Arthritic/axial/mechanical neck pain is not an indication for TDA, nor would it be for the ACDF procedure. (You would think something that looks like a “knee replacement for the neck” would also relieve arthritic neck pain, but it probably won’t.) To emphasize, these are not operations to treat neck pain from arthritis. If neck pain is your main problem, disc replacement won’t solve this. Disc replacements are operations for nerve pain (down the shoulders or arms).

The two main advantages of TDA over fusion would be quicker return to function or work (i.e., no wait time for biological fusion) and preservation of motion. The theoretical advantage of TDA is that we will see less adjacent- level disease develop down the road, and presumably less redo surgeries.

Dr. Urquia is trained in the cervical TDA procedure since 2010, has implanted the Prestige ST device (Medtronics) , the Prestige LP (Medtronics), and the Mobi-C device (LDR). He is also certified to use the Depuy- Synthes device – ProDisc-C.

The Mobi-C device and Prestige LP currently are approved for 2-level applications. Prestige LP is a titanium alloy and has the best MRI compatibility. Other devices might require the use of CT-myelogram imaging technology instead of MRI, if down the road new scans of your neck are needed. To be clear, you are usually safe to have an MRI with any of these TDA devices, it’s just that MRI images of the neck are too distorted to read for some implants because of the types of metals used.

Patients approved for TDA will also be consented for possible ACDF, because until we actually get into the operating room, take X-rays and directly inspect the bone we can’t be 100 percent sure a TDA can be performed. Occasionally the patient is found to have too much arthritis during surgery, or poor quality bone, or they are too overweight with big shoulders blocking the necessary precise X-rays required for TDA. In such cases, we perform fusion (ACDF) instead.

David Urquia, MD