Current Trends and Evolution of Artificial Disc Replacement

While degenerative disc disease isn’t inevitable as you age, it’s awfully common. Consider this — more than 90% of older adults show signs of degeneration in their discs. While many of these people don’t develop any symptoms, many others do, and these symptoms are life-altering, though life-limiting is a more appropriate description.

Traditionally, problems with advanced degenerative disc disease (DDD) have been resolved through spinal fusion, but more surgeons are turning to disc replacement as artificial disc technologies advance and patients are seeing great results.

Here at our practice, board-certified neurosurgeon Dr. Ali H. Mesiwala is pleased to be a part of this trend as he provides patients with new hope through artificial disc replacement.

Here’s a look at how artificial disc replacement is changing the way we’re solving the DDD puzzle.

A look back at spinal fusion

As we mentioned, the frontline treatment for advanced DDD, both lumbar and cervical, has been fusion, a technique in which we remove the damaged disc and fuse the two vertebrae together. While this approach has been effective in reducing symptoms, such as back or neck pain as well as radiating pain in the limbs (radiculopathy), it’s not without some complications.

Our biggest concerns when it comes to spinal fusion are the loss of range of motion in the spine and the potential for more issues down the road. More specifically, when two vertebrae are fused together, it creates a larger structure, and this new, longer segment now places more pressure on the discs on either end of the fused vertebrae. 

This complication is called adjacent segment disease, and it isn’t uncommon. One analysis of more than 1200 patients found that adjacent segment disease affected between 5% and 49% of them after lumbar spinal fusion.

Recognizing that spinal fusion may be only offering a short-term fix that may lead to bigger problems down the road, our focus has turned to artificial discs.

The coming of age of artificial discs

The discs in your spine are more than just spacers that divide and support the vertebrae in your spine. These discs work with your spine, expertly transferring loads to enable movement while they provide enough cushioning and space to keep sensitive nerve roots and fibers free from entrapment.

The discs in your neck and lower back are the ones that succumb to degeneration sooner since these are areas of your spine that enjoy the most movement.

As you might imagine, figuring out a way to replace these discs with a satisfactory substitute is the real key to solving DDD.

The good news is that we’re getting better at it every day. Back in 2007, the FDA approved the first artificial cervical disc and, since then, eight more artificial discs have received approval as the technology improves.

The first artificial lumbar discs were approved by the FDA even earlier in 2004. Today, new artificial lumbar discs are hitting the market, and the FDA has even approved some for two-level replacement (meaning we replace two discs at once).

Whether cervical or lumbar, these artificial discs come in 

different sizes to achieve optimal coverage and spacing between vertebrae to relieve nerve compression. The materials that are used in these discs include:

• Polyethylene for load transferring
• Titanium for strength
• Corrosion-resistant cobalt-chrome
• Stainless steel

Now let’s take a look at the early success of these artificial discs.

Early results of artificial discs are favorable

While long-term results are tough to come by since we’re dealing with a newer technology and procedure, what we’ve seen so far is very impressive.

For example, one study that compared two-level total cervical disc replacement to cervical spinal fusion surgery found that replacement offered higher success rates. At the two-year mark, improvements in neck disability were found in 92.9% of the disc replacement group versus 83.5% in the fusion group.

An observational study reported that replacing a lumbar disc led to reduced costs and length of hospital stay, as well as lower rate of blood transfusions as compared to lumbar spinal fusion.

Our point in highlighting these two studies is to emphasize a few points that support artificial disc replacement over spinal fusion, such as:

• Artificial disc replacement can better relieve the symptoms of DDD 
• There’s less adjacent segment disease with disc replacement
• The disc replacement procedure carries less risk and less hospitalization time than spinal fusion

While artificial disc replacement technologies continue to improve, we’re sure these results are only going to get better.

Currently, Dr. Mesiwala has been following all of his disc replacement patients for nearly 15 years that he has been performing these procedures. More of these disc replacement operations are taking place in the outpatient setting, with patients going home the same day. They have minor restrictions for a few weeks while the artificial disc is completely integrated and the surrounding tissue has healed. On average, patients are returning to an unrestricted lifestyle of all activities within 2-4 weeks after surgery. We regularly follow all of our patients on post-operative timeline to ensure a consistent and optimal recovery. 

Dr Ali H. Mesiwala is also part of on going research to advance the field of motion preservation medicine. Currently he is participating as a principal investigator on the Orthofix M6C 2 Level IDE study and enrolling patients. Patients have to under go routine pre-operative evaluation and determination of meeting all eligibility criteria set forth by the FDA and the sponsor. In addition to that he is also involved with research regarding the Nuvasive Simplify disc which he has implanted over 500 of. 

Artificial disc replacement has evolved quite a bit over the past decade and continues to evolve. Patients are typically candidates with good disc height and joints having been diagnosed with degenerative disc disease with or without radiculopathy or myelopathy. 

If you’d like to explore for yourself whether artificial disc replacement is a better solution for your DDD than spinal fusion, we invite you to contact one of our offices in Newport Beach, Marina del Rey, or Rancho Cucamonga, California, to schedule a consultation.