Cervical Spine Reanimation – Dr. Larson Navigates a New Frontier in Spine Surgery!

Humans are the only continuously biped creatures on earth. To maintain this biped stance and be able to stand upright and walk on 2 feet requires balance, posture, and coordination. There is a delicate intercommunication between the head, all parts of the spine, the pelvis, the hips, the knees, and the ankles and feet to ambulate with this posture. Horizontal gaze is the product of a harmonic symphony between all of these body parts. If one-part falters, the others must accommodate or horizontal gaze will be lost, and the body will no longer follow the rules of bipedal balance. You begin to hunch forward, lean against the grocery cart or counter, and progressively become less ambulatory.

The cervical spine has a key role in posture and in particular something called “horizontal gaze”. This is simply looking straight ahead parallel to the ground surface. This obvious and seemingly simple function is actually complex.

The Cervical spine is made up of a complex set of bones called cervical vertebra. The upper cervical spine, C1 and C2 act to support the head and let it rotate on the spinal axis. The mid cervical spine, C3-C7 are mostly involved in flexion and extension and play a key role in cervical posture. The lower cervical spine, C7 connects the cervical spine to the thoracic spine.

C1 and C2 make up the atlantoaxial joint. Different from the other cervical vertebra, the purpose of this integrated pair of vertebrae is to connect the head to the spine and let it rotate. The vertebral arteries course through the cervical spine and exit here and travel dorsal to the posterior arch of C1 before piercing the dura and going to their destination in the brain. These vertebrae are susceptible to certain types of trauma that involve shift or impact to the weight of the head. They are also susceptible to some arthritic and inflammatory conditions due to the multitude of ligaments and joints involved in head rotation.

The mid cervical spine spans C3-C7. It plays a huge role in posture, and it is also vert exposed and vulnerable to whiplash, disc herniation, and degenerative disc disease. Pain from this area may radiate superiorly to the posterior skull to cause headaches, and inferiorly and laterally into the shoulder blades, trapezius, shoulders, and arms. Chiropractors, physical therapists, and massage therapists often treat the midcervical spine and its supporting muscles and ligaments with exercise, traction, and manipulation. The spinal cord and nerve roots are susceptible to compression and pressure from bone spurs, disc space narrowing, kyphosis, disc herniation, stenosis, and instability in its path through the mid-cervical spine. When this level of problem occurs its often time to consider surgical correction.

This leads into the topic of this blog and let me be very clear here. If you are diagnosed with a midcervical spine condition that needs surgery, you need to know all of your options. Not all surgeries are the same and the type of surgery you choose will have great impact on your quality of life after the surgery. YOU HAVE CHOICES! The lower cervical spine, C7 facilitates the transition to the thoracic spine. This cervical-thoracic junction is generally very stable and not susceptible to injury or wear and tear like the other levels.

As a spine surgeon, performing cervical spine surgery provides some of the most gratifying results in all that we do. Patients transition from severe pain and disability to a sometimes pain free and normal life promptly after surgery. The degree of positive change and gratification is so extreme that cervical spine surgery has become a favorite surgery for most spine surgeons.

I have watched cervical spine surgery evolve from posterior approach to anterior approach during my medical school years. I participated in and witnessed the introduction of anterior cervical plating during my neurosurgery residency years. I applauded the introduction of interbody cages and biologics making a hip graft obsolete when I started my clinical practice in 1997. And I welcomed the introduction of artificial cervical discs (ADR) in 2006 to possibly replace cervical fusion as standard of care treatment.

I often tell the story of a patient of mine, Nick who was an early cervical ADR case of mine, and he was one of the first cervical ADR workers compensation case in Idaho. Nick came to my office in October or November of 2007. There is a fun video where he tells his story (see Nick’s story here).

In short, Nick was treated by an orthopedic surgeon for a shoulder problem occurring after a snowboard injury. He even had shoulder surgery but didn’t get better. Snowboard season was coming back around, and Nick was so disappointed after a cervical MRI showed a disc herniation that was causing his problem. Now this is back nearly a couple decades ago when the cervical ADR was new. So new, that even though it passed its IDE studies in flying colors, was FDA approved, and had already enjoyed success around the world, US insurance companies still called it “investigational” and made it nearly impossible for surgeons to get them authorized. This was not the case for some of the worker’s compensation programs like the one here in Idaho.

The Idaho Workers Compensation and the Idaho Industrial Commission are exemplary in their efficiency and care with the worker and employer alike. In my experience they have the patient’s performance in mine. This team develops relationships with the patient, the employer, and also the treating doctors and surgeons.

I had such a relationship with them at the time of treating Nick, and I continue to enjoy this relationship and the opportunity to treat injured workers now. Well, after a conversation with the claims adjuster and the nurse case manager, I got authorized to perform a cervical ADR on Nick, and it was to be the very first for them in Idaho. No pressure, right? I had promised Nick there would be no delay to surgery on my part if the cervical ADR was approved. Authorization came December 23, and true to my word I did his surgery Christmas Eve, December 24! Holly NP and I still smile about it now when we think about our cervical ADR journey and where we are going with it now! The rest is history. Nick is thriving without limits. I wished him a Happy Thanksgiving by text today, Thanksgiving 2024 and he shared his thanks for how I treated with a cervical ADR 2 decades ago.

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I was ready to perform surgery that Christmas Eve day. I had developed and honed my anterior cervical discectomy (ACDF) technique, and cervical ADR followed the same principal. Remove the damaged disc and stabilize the segment, but this time with a dynamic artificial disc, instead of a fusion graft or cage. In the case of Cervical ADR however, precision surgery brings into an interpretation of the normal motion of the neck and how it will change with the controlled motion of the artificial disc. It’s not just a hinge in the spine, it’s a symphony of motion between the disc, the facet joints, and the uncinate joints at the now dynamically stabilized level. This was precise, and I love precision. As you see, it did the job for Nick!

Since then, Nick and thousands of other patients are living life to its fullest without restrictions after a successful cervical ADR. I was intrigued by the early results, so I retrospectively reviewed my own results for cervical ADR surgeries in workers compensation patients and found that although both ACDF and cervical ADR patients did well and were able to return to work. This was a good study group because these timepoints are accurately followed in days. What I found was that the return-to-work time for single level cervical ADR was 28 days on average vs 71 days on average for ACDF. I reported this at the 2015 International Society for the Advancement of Spine Surgery Annual Meeting. Abstract and Oral Poster presentation. Return to Work Comparison for Workers Compensation Patients Treated with Cervical Disc Arthroplasty versus Anterior Discectomy and Fusion. (San Diego, California. April 15, 2015.)

Put yourself in that position after a delicate cervical spine surgery. Return to full activity with no restrictions after 4 weeks! I started to feel like I was actually curing a disease or problem!

Still, even with these amazing life changing results, sadly, many commercial insurance companies and even many surgeons have been slow to adopt or even refuse cervical ADR technology.

In conversation with insurance companies, they have no answer. They just call it “investigational”, a word that is not substantiated by any objective answers, and generally given to me by a non-clinical representative. They often limit ADR to very basic cases, while allowing fusion across the spectrum of cervical spine problems. I don’t think I have ever heard a representative of an insurance company ask, “shouldn’t this patient be considered for a disc replacement instead of a fusion”. I frequently have to appeal cervical ADR denials, but much less often get a denial when requesting an ACDF.

In the case of motion preservation resistant surgeons (sounds like a disease, doesn’t it?), I have not yet heard an eloquent explanation. It is my observation, however, that it is the same crowd that would in general do a 360-degree lumbar fusion vs. elegantly removing an extraforaminal disc herniation in a patient with a simple radiculopathy. If you are in this circle, you know the meme. Fortunately, more spine surgeons are getting on board with cervical ADR as a valid option, and even the gold standard surgery to treat cervical disc herniation with radiculopathy or myelopathy in patients who have not improved with non-operative treatments and are surgical candidates. There are more and more clinical studies supporting this trend.

Generally speaking, selection of ADR is focused on an injured disc with limited deterioration of the other supporting structures of the cervical spine, in particular, the uncinate joints and the facet joints. These are the joints to the sides of the disc and behind the disc in the back of the spine. The theory here being that if there is pain related to an arthritic condition in these joints, that replacing the disc alone with a movable part may further aggravate the painful motion, while fusion may eliminate it. In these cases, stabilizing the injured disc with a cage for fusion may be more appropriate.

Don’t entirely fear the idea of ACDF. This surgery too has evolved in regard to the instrumentation used and the surgeon attention to a minimally invasive approach so there is still great success! My suggestion is simply to ask your surgeon about cervical ADR and decide from there.

So, what are the limits of cervical ADR? Insurance companies have their limits, and surgeons generally follow these enforced and often unsupported limitations largely because the insurance companies control payment of the procedure. Regardless, surgeons like me will share opinions with patients as to “best treatment” independent of the insurance company guidelines. It is likely this type of surgeon honesty and drive that moves the needle, and it appears the needle is moving toward cervical ADR!

There are at least 8 different FDA approved cervical ADR devices, and more in the pipeline. All of these cervical ADR implants share the same philosophy of motion preservation. The different implants, however, have great variability in materials, function, footprint, degree of motion, and how it is secured into the cervical spine. This variability opens up the door to case-by-case considerations. I have used each of the available cervical ADR implants with success and continue to tune my treatment algorithm with experience.

For example, there is clearly more upper limit to the degree of cervical degeneration that could be treated by cervical ADR instead of ACDF. Some surgeons will go so far as to convert an ACDF to an ADR. I will hold opinion of this for now but will strongly support that treating a symptomatic adjacent level to an ACDF with a cervical ADR is an excellent option. It is intuitively obvious that this idea may stop the progression of degeneration by preserving motion with an ADR.

I have expanded treatment indications of cervical spondylosis with ADR. This surgical evolution comes with the expanded experience and skill of meticulously decompressing the spinal cord and nerve roots for optimal neurological recovery and the availability of different cervical ADR implants to support this push to “reanimating” an injured cervical spine.

This is very exciting to me, as motion is a pillar of life.

Until next time,

Jeffrey Larson, MD
The Tall Spine