The M6 cervical artificial disc has just gained FDA-approval to be used in the United States! And our site (Dr. Todd Lanman and myself) has been chosen as the first site to be able to use the disc in our patients.
Dr. Cuéllar and his partner Dr. Lanman are experts at artificial disc replacement for the relief of neck or back pain while maintaining spinal motion.
Artificial Disc Replacement Compared to Spine Fusion
Total replacement of a spinal intervertebral disc is known by several terms, such as total disc replacement (TDR), artificial disc replacement (ADR) or total disc arthroplasty (TDA). All of these terms refer to the same thing – removing a diseased intervertebral disc and replacing it with a device made mostly of various mixes of medical grade metal. Sometimes the device also contains a part which is made of specialized wear-resistant plastic referred to as high-molecular weight polyethylene – the same material used in total hip and total knee replacements.
Why do I think total disc replacement is better than fusion when appropriate?
Our spines are meant to move. Each intervertebral segment is made up of two complex shaped bones called vertebrae that form several joints with each other (see diagram below). In the back (posterior) aspect of the spine there are two joints called facet joints. In the front (anterior) aspect of the spine there exists an intervertebral disc that sits between the two vertebrae that compose the spinal segment. This disc acts as a shock absorber for your body weight, and allows motion such as forward bending (flexion), backward bending (extension), side bending and rotation.
What happens when one or more levels of the spine are fused together?
Sometimes it is necessary to fuse one or more levels of the spine together, such as when there is instability between these levels. One potential downfall to this procedure, however, is accelerating the rate of degeneration of the next (adjacent) level. Although we all have some level of spinal degeneration over time, some studies have demonstrated that fusion at one level may accelerate the rate of degeneration at the adjacent level, likely due to increased stress at that level:
Compare this to an artificial disc replacement:
More spinal motion is maintained after a disc replacement compared to after a fusion. This continued motion attempts to replicate your natural spinal anatomy and physiology. Disc replacement at one level does not result in as much increased stress at the adjacent level and therefore is less likely to accelerate the degenerative process at that adjacent level. Long-term studies are starting to demonstrate that years after surgery, disc replacement patients have lower rates of accelerated adjacent disc degeneration compared to patients that underwent fusion surgery.
Lumbar artificial disc replacement in the athlete:
Patients often ask me if they can run and perform other sports at a high level after their total disc replacement surgery. The answer is yes! Here is a great paper by Siepe and colleagues (Munich, Germany) looking at a group of athletes that underwent total disc replacement surgery. Almost all of them, with a few exceptions, were able to get back to it at a similar performance level without limitations.
Cost-effectiveness of artificial disc replacement: Not only is evidence mounting that in the long-term, artificial disc replacement is superior to fusion, several excellent studies have demonstrated that it is more cost-effective!
Disclaimer: Dr. Cuellar is here to help with your medical condition. However, any medical advice dispensed on this website is not an official medical opinion because the doctor has not performed an in-person history and examination. If you need specific medical advice, please make an office appointment.