Cervical Spondylotic Myelopathy: Evolution of Treatment

Podcast Transcript

Neuro Pathways Podcast Series

Release Date: March 15, 2025
Expiration Date: March 14, 2026

Estimated Time of Completion: 30 minutes

Cervical Spondylotic Myelopathy: Evolution of Treatment
Thomas Mroz, MD

Description
Each podcast in the Neurological Institute series provides a brief, review of management strategies related to the topic.

Learning Objectives

• Review up to date and clinically pertinent topics related to neurological disease
• Discuss advances in the field of neurological diseases
• Describe options for the treatment and care of various neurological disease

Target Audience
Physicians and Advanced Practice providers in Family Practice, Internal Medicine & Subspecialties, Neurology, Nursing, Pediatrics, Psychology/Psychiatry, Radiology as well as Professors, Researchers, and Students.

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• American Medical Association (AMA)
  Cleveland Clinic Center for Continuing Education designates this enduring material for a maximum of 0.50 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
  
  Participants claiming CME credit from this activity may submit the credit hours to the American Osteopathic Association for Category 2 credit.

• American Nurses Credentialing Center (ANCC)
  Cleveland Clinic Center for Continuing Education designates this enduring material for a maximum of 0.50 ANCC contact hours.

• Certificate of Participation
  A certificate of participation will be provided to other health care professionals for requesting credits in accordance with their professional boards and/or associations.

• American Board of Surgery (ABS)
  Successful completion of this CME activity enables the learner to earn credit toward the CME requirements of the American Board of Surgery’s Continuous Certification program. It is the CME activity provider's responsibility to submit learner completion information to ACCME for the purpose of granting ABS credit.

Credit will be reported within 30 days of claiming credit.

Podcast Series Director
Andreas Alexopoulos, MD, MPH
Epilepsy Center

Additional Planner/Reviewer
Cindy Willis, DNP

Faculty
Thomas Mroz, MD
Center for Spine Health

Host
Glen Stevens, DO, PhD
Cleveland Clinic Brain Tumor and Neuro-Oncology Center

Agenda

Cervical Spondylotic Myelopathy: Evolution of Treatment
Thomas Mroz, MD

Disclosures

In accordance with the Standards for Integrity and Independence issued by the Accreditation Council for Continuing Medical Education (ACCME), The Cleveland Clinic Center for Continuing Education mitigates all relevant conflicts of interest to ensure CME activities are free of commercial bias.

The following faculty have indicated that they may have a relationship, which in the context of their presentation(s), could be perceived as a potential conflict of interest:

Thomas Mroz, MD	Stryker Intellectual property rights (Royalties or patent sales)
Glen Stevens, DO, PhD	DynaMed Consulting

All other individuals have indicated no relationship which, in the context of their involvement, could be perceived as a potential conflict of interest.

CME Disclaimer

The information in this educational activity is provided for general medical education purposes only and is not meant to substitute for the independent medical judgment of a physician relative to diagnostic and treatment options of a specific patient's medical condition. The viewpoints expressed in this CME activity are those of the authors/faculty. They do not represent an endorsement by The Cleveland Clinic Foundation. In no event will The Cleveland Clinic Foundation be liable for any decision made or action taken in reliance upon the information provided through this CME activity.

HOW TO OBTAIN AMA PRA Category 1 Credits™, ANCC Contact Hours, OR CERTIFICATE OF PARTICIPATION:

Go to: Neuro Pathways Podcast March 15, 2025 to log into myCME and begin the activity evaluation and print your certificate If you need assistance, contact the CME office at myCME@ccf.org

Copyright © 2025 The Cleveland Clinic Foundation. All Rights Reserved.

Introduction: Neuro Pathways, a Cleveland Clinic podcast exploring the latest research, discoveries and clinical advances in the fields of neurology, neurosurgery, neuro rehab and psychiatry.

Glen Stevens, DO, PhD: Cervical spondylotic myelopathy is the leading cause of spinal cord impairment in adults over age 55. While surgeons have developed an impressive range of treatment options over the last few decades, the variety of available approaches raises important questions. What distinguishes these different surgical techniques? And more crucially, how do we determine the optimal approach for each patient?

In today's episode, we're exploring the surgical landscape of cervical spondylotic myelopathy treatment, examining current advancements and promising research developments. I'm your host Glen Stevens, neurologist, neuro-oncologist in Cleveland Clinic's Neurological Institute. I'm very pleased to be joined by Dr. Tom Mroz for today's conversation. Dr. Mroz is a spine surgeon, Chairman of the Orthopedic and Rheumatologic Institute, and Director of Spine Research at Cleveland Clinic. Tom, welcome to Neuro Pathways.

Thomas Mroz, MD: Thanks, Glen. It's a real pleasure to be here.

Glen Stevens, DO, PhD: So Tom, just to start things off so that our audience gets to know you a little bit, tell us a little bit about yourself: where you came from, how you came to the clinic, and what your role is at the clinic.

Thomas Mroz, MD: Sure. Well, I'm a Cleveland native. I went to medical school here at Case. I did my residency training in orthopedic surgery at George Washington in DC. Did one fellowship at UCLA and then another fellowship with a neurosurgeon doing spine surgery and minimally invasive surgery in Memphis, Tennessee. Then I landed here in 2004, and I've been here ever since.

Glen Stevens, DO, PhD: Good. Well, one of the things I've always been impressed with the program here is actually the commingling of the surgeons and the orthopedic. So combining the neurosurgeon and the orthopedic surgery fellowships and training I think is fantastic.

Thomas Mroz, MD: Yeah, absolutely. Ed Benzel, Iain Kalfas, and Gordon Bell, the latter of which was an orthopedic surgeon and the previous two were neurosurgeons, did a really great job in 2006 in bringing both pedigrees together in a unique way that really transformed expectations across the country of what we could do.

Glen Stevens, DO, PhD: So to start the conversation today, so those that are unfamiliar with what we're talking about, tell us what cervical spondylitic myelopathy is and the types of symptoms that might bring someone in to see a physician.

Thomas Mroz, MD: Sure. Cervical spondylitic myelopathy is a relatively common condition, which patients typically become affected in the fifth, sixth, seventh, and eighth decades of life. But what it really means… it means dysfunction of the spinal cord. And that can come in a variety of different ways and be caused by different things. But in general, when you have the spinal cord being compressed, typically it's by an arthritic process that causes a diminution in the area of the spinal canal in the neck. The spinal cord starts to malfunction. And the most common features of that are loss of hand dexterity, diffused numbness in the hands typically. But we see odd areas of other parts of the body becoming numb, vibratory sensations. And a couple of the other hallmarks are balance and gait problems. Typically, we ask patients very typical questions, "Do you have any falls? Are you losing your balance? Can you button your buttons? Can you hold a spoonful of soup without spilling it?" Those sorts of things. But it's the upper and lower extremity dysfunction that heralds the spinal cord compression and dysfunction.

Glen Stevens, DO, PhD: Well, as I'm getting into those decades that you mentioned, it's becoming more important to me. So I pay more attention to this type of stuff. And of course for our listeners out there, myelopathy, we're just referring to problems affecting the spinal cord, which we differentiate from radiculopathies that are affecting the nerve roots. How often do you actually see cord injury with people that are symptomatic?

Thomas Mroz, MD: Well, I think it happens on a spectrum, but when patients have spinal cord dysfunction, it is on the spectrum of spinal cord injury. The good news is when we catch patients earlier on in the continuum or the spectrum of spinal cord dysfunction and intervene surgically, and we can get to that in a moment, typically patients can revert almost back to normality if their dysfunction to begin with is not so severe.

Glen Stevens, DO, PhD: And I assume other causes besides just the arthritic changes, people have rheumatoid arthritis, a little more risk in my field. Tumors could cause a similar problem. Trauma could cause a problem. What do you see mostly in your practice?

Thomas Mroz, MD: All I do is cervical spine, but we see a variety of different things. Spinal cord tumors, metastatic disease also can cause spinal cord compression and subsequent dysfunction. Infections and epidural abscesses, which we see here at the clinic relatively frequently also can cause compression and dysfunction. And obviously, as you mentioned, the spinal trauma that we sometimes see can injure the spinal cord, as well.

Glen Stevens, DO, PhD: So, I'm getting older. I think that I'm having some bilateral symptoms. My gait's a little off, maybe having some other types of minor symptoms... I probably come to see my primary care physician first. But if they come to see you first… besides doing obviously a good neurologic exam, what type of tests are you doing on these folks?

Thomas Mroz, MD: Yeah, there are really two important tests, one of which is X-rays, just to understand the alignment of the spine. As you mentioned, rheumatoid arthritis, we see very hallmark characteristic findings of rheumatoid arthritis with regard to the structure of the discs and the bones. But when we evaluate the spinal cord, we're always going to be getting an MRI. And in some patients, a minor percentage of patients, will have to get a CT myelogram. But hallmarks are going to be then X-ray and an MR MRI.

Glen Stevens, DO, PhD: So you'd see me, and I've got some symptoms. You do some imaging, things look a little tight up in the neck. How do you decide if I should have surgery?

Thomas Mroz, MD: That's a great question. First and foremost, part of the history that's really important is not only the presence or absence of the cardinal signs and symptoms of spinal cord dysfunction but whether or not they've progressed. And I typically ask patients over the past 12 months if it's progressed. Because if it's progressed, then we know that you're falling more into a surgical category. But because we also know roughly 5% to 10% of patients that can enter a quiescent period of time where their symptoms stay static.

But we also have more sophisticated measures, one of which is the modified JOA, which is actually developed by Dr. Benzel here at the Cleveland Clinic. That is an outcome measure that all patients before they see me and other surgeons here at the Cleveland Clinic are measured, and we score them numerically. And if you fall within a normal range or a minimally affected range, that tells us maybe you are one of the patients that we can watch over time. But if you fall in the moderate or even severe range, particularly when that's coupled with progression of the disease or your symptoms, then we typically will recommend surgery for that.

Glen Stevens, DO, PhD: What type of things are on the scale?

Thomas Mroz, MD: It's use of hands, it's the ability to walk without any significant dysfunction. Those sorts of things, but primarily the upper lower extremity function.

Glen Stevens, DO, PhD: So I come see you, I'm sort of in the middle. So whatever that number is, I'm kind of in the middle. I could go either direction with it. If I do physical therapy, will that help? Or I guess it depends a little bit on the exact cause, but does it help?

Thomas Mroz, MD: Sure, if you're mild with regard to the degree of impairment, physical therapy can help compensate for what's happening. But physical therapy alone, nor bracing, nor any sort of medication is going to change what's happening to the spinal cord per se. But you can with physical therapy compensate if you have a mild impairment due to the spinal cord compression and myelopathy.

Glen Stevens, DO, PhD: So, if I show up to clinic with my neck brace on, it's probably not doing what I needed it to do.

Thomas Mroz, MD: No, typically not. No, it's not the standard of care to recommend bracing for patients with myelopathy.

Glen Stevens, DO, PhD: And just as a little aside, I guess. If you have tightness that are there, does it limit my activities?

Thomas Mroz, MD: Sure, that's a great question, particularly in younger populations who are very active. For patients who have spinal cord compression and who have some symptoms or signs on examination… So if a patient is hyperreflexic or they have pathological reflexes suggesting they have spinal cord compression, I will typically tell those patients to avoid activities that put them at risk for a fall: jet skiing, water-skiing, aggressive skiing or snowboarding, those sorts of things because we don't want to run the risk of them having a fall and you sudden suddenly hit your head or jar your neck or in an extreme motion that could put you at risk for a variety of different spinal cord injury syndromes, most typically central cord syndrome.

Glen Stevens, DO, PhD: And Cedar Point probably isn't a big fan of yours either, right? We stay off the roller coasters?

Thomas Mroz, MD: I get that all the time, and I like going by the peer-reviewed medical literature. But we don't have any literature suggest whether or not we should actively bar patients. But in patients who are moderate or severe with regard to their function, I typically will say stay away from roller coasters, only because some of it's unpredictable.

Glen Stevens, DO, PhD: Okay. So, I come to see you, I'm in the middle, I do a little bit of therapy. I'm doing pretty good, but my symptoms are slowly starting to progress over time. And now you're thinking I might need to do something surgical. What's the discussion that we have?

Thomas Mroz, MD: Yeah, there are many factors that go into deciding. Number one, does a patient need surgery? And if the patient needs surgery, what type of surgery there are? And primarily there are three different types of surgery that we do for this. And we try to tailor the type of surgery to the vocation and the activity level of a patient. But also it's in large part dictated by the pathology that they have and the alignment of their spine that they have.

But in general, of the three main types, there's an anterior approach which typically will require a fusion, possibly if it's one- or two-level disease, disc replacement surgery. But there are also two options coming in posteriorly, one of which is a laminectomy infusion, and the other one is going to be a laminoplasty. They're very different procedures, so any fusion from the front is similar to a fusion from the back, but that's going to eliminate your motion.

And so, going back to my previous point, if you're a very active person who likes to hike or if you're a 50-year-old that is a vocational painter and needs a full range of motion of your neck, typically a long segment fusion in the front or the back of the neck is probably not the ideal option. Enter in laminoplasty, which is a posteriorly based procedure, which is very different. It was developed decades ago in Southeast Asia. But it's a motion preserving technique where we just change the geometry of the spinal canal by way of working at each individual level that is compressed and then opening up the canal.

Glen Stevens, DO, PhD: So, you're just thinning it out.

Thomas Mroz, MD: Actually…

Glen Stevens, DO, PhD: The bone or no?

Thomas Mroz, MD: No, on the laminoplasty, we're making a full cut on the lamina, for example, on the left side and a partial on the right. And we just open up the bone, kind of like a hinge. And it's basic geometry, pi r squared. You increase the radius of roughly a circle and you increase the surface area by a significant degree.

Glen Stevens, DO, PhD: And a laminectomy... The difference with that and an actual laminectomy is what?

Thomas Mroz, MD: Yeah. So with the laminectomy fusion, we would do a full laminectomy and instead of preserving motion at each individual level, we place screws up and down the posterior spine and apply rods permanently fixing the spine in a certain position.

Not all patients are a candidate for laminoplasty. It is somewhat dictated by the degree of neck pain a patient has. And typically if patients have a low or moderate degree of neck pain and their alignment is acceptable, meaning it's got to be straight up and down, or it's got to be slightly tilted back, we call that lordotic, which is a normal type of alignment. Those patients are more prone to having a laminoplasty. My go-to procedure for patients who have multilevel spinal cord compression is going to be a laminoplasty because I think motion preservation is really important, the function of life, particularly in an active patient.

Glen Stevens, DO, PhD: Now some people have congenital cervical stenosis. Percent of those that will end up having that something done? Do we have any idea what that is?

Thomas Mroz, MD: That is a fantastic question. Something that we've looked at in the lab. the prevalence of congenital stenosis is somewhat nebulous right now, but it's not a disorder. It's a normal variant of human beings. Sometimes patients have just a normal bony canal that predisposes them as they age to developing spinal cord compression and subsequent myelopathy at an earlier age than patients who have a normal bony canal.

Glen Stevens, DO, PhD: Yeah, I remember a couple of times I've heard NFL players have a head contact injury and then someone images them and they go, "Oh, you had a congenitally narrow cervical canal, and that's probably why you're a little more risk."

Thomas Mroz, MD: Yeah, absolutely. The NFL players are an interesting group, as are rugby players. They are a population of humans that become symptomatic sooner because they have the contact, and not that they have a more early degenerative process instead Because of the vocation and their athletic activities. They become symptomatic at an earlier age.

Glen Stevens, DO, PhD: Well, I'll consider myself lucky because I was a Division I rugby player in university many years ago, but maybe I need an image.

Thomas Mroz, MD: Well, maybe you don't have congenital stenosis.

Glen Stevens, DO, PhD: I'll be lucky if I don't. But just to stick on the congenital stenosis for a minute, if they have to have something done surgical and you've got a long segment that's there, could you still just do a one or two level segment that's the tightest? Or do you really need to do a full?

Thomas Mroz, MD: Yeah, that is also a great question. I think in part you were a spine surgeon in your previous life. But the reality of it is there's some debate among spine surgeons across the country, in that for people who have congenital stenosis and they have say two-level disease, some say you should treat the global problem and ideally it would be a laminoplasty. On the other hand, others will say, "Well, let's just go ahead and treat it focally through an anterior approach.” It's a very simple, predictable operation, and if they break down at a subsequent time, they can have a laminoplasty in the future or a laminectomy infusion in the future. But what we try to do in spine surgery, particularly for patients with myelopathy, is we want to make whatever surgery we design for a time point A to be the last surgery period. We want to make sure it's durable as possible. And so from my perspective, if the patient has two-level disease, and I think you can make an argument to do a laminoplasty on those types of patients as well, as long as everything else fits.

Glen Stevens, DO, PhD: And if when I come to see and I've got my arthritis, is there a specific cervical level that it's mostly at? Is it mostly at C3-4, 4-5, 5-6? Is it variable right at the junction of the thoracic or...

Thomas Mroz, MD: Yeah, absolutely. The good news is that human beings are a relatively consistent species and that the C5-6 and C6-7 are typically the levels that break down first from a disc degeneration perspective. And by way of that, it's typically those levels that become stenotic first and then it works its way up. And over time, what we see is that the spine becomes stiffer with time. So if 5-6 and 6-7 are breaking down, they too are also becoming stiffer, which predisposes to C4-5 biomechanically to see more of those loading. Because people continue to live their life, move their head around, and the loading stays the same if not enhanced at the cranial level or the caudal level below the stiff level. And so yes, we do see that, but it's 5-6 and 6-7 that go first.

Glen Stevens, DO, PhD: So assuming I don't have rheumatoid arthritis, what's the likelihood I have stenosis in my thoracic or lumbar area that we'll need to have something done surgically? Or not correlating?

Thomas Mroz, MD: I couldn't give you an incidence of need for surgery, but it's going to be very low.

Glen Stevens, DO, PhD: Okay.

Thomas Mroz, MD: The majority of human beings don't need spine surgery on their neck.

Glen Stevens, DO, PhD: And recovery from the spine surgery?

Thomas Mroz, MD: Sure. Regardless of which surgery you have, from the front or two of the possibilities from the back. Typically, we tell patients you're going to be in the hospital for two or three nights, and then we start physical therapy right away. For two reasons really, to make sure mentally they are feeling like they're making progress, but literally so that they do make progress in retraining their body to function even though they've got some spinal cord impairment. And we see over time that within the first six weeks after surgery, the patients do quite well. I mean there's really a remarkable improvement in neurological function. And then they start to plateau and those gains, while they still are apparent, become much slower. And so when I see patients at six weeks, they're very happy, like, "Wow, I have a big difference in the sensation of my hands," or "My hands are functioning better." And if they're weak, they are potentially getting a little bit more improvement with their strength. And then I see them at six months and then they still have some impairment and I think they forget of how impaired they were before surgery. But that's only to highlight that at roughly the six-week mark, their gains become a little bit less slow.

Glen Stevens, DO, PhD: I see this with patients as well all the time, and we have this discussion with people. That things that aren't a problem for you now may become a problem later as we fix something. That's resolved, so whatever is number two or number three on your list now becomes number one. So that's your center of attention.

Thomas Mroz, MD: That's right.

Glen Stevens, DO, PhD: And then you have to sort of help people understand, was it always there and it's just now the more common problem.

Thomas Mroz, MD: That's right.

Glen Stevens, DO, PhD: If I have a little cord edema after surgery, does that get better or you'll usually still see a remnant?

Thomas Mroz, MD: Great question. And there's a couple of really great papers that came out over the past five years that looked specifically at the presence of cord edema and its resolution post-surgery. But what they've essentially arrived at is that if the edema is very intense and it spans a larger section of the spinal cord, those are the types of lesions that don't get better. But it's the smaller lesions, the more focal and contained lesions that will resolve, and typically they'll resolve in a few months.

Glen Stevens, DO, PhD: Yeah, it's interesting. I saw a patient when I was on hospital service a number of years ago that got transferred into the neurosurgery service. And I got asked to see the patient because they had signal change in their cervical cord. And again, they had some arthritic changes and the thought was, “Did this ding the cord?” But fortunately, the neurosurgeon was a little suspicious that maybe it just didn't seem to quite make sense. And we evaluated and worked the patient up and they had the old version of neuromyelitis optica spectrum disorder when we did antibody testing. So surgery would've been the absolute wrong thing to do on that patient. So occasionally we get fooled on these things and when it doesn't make sense, it's always worthwhile to look at other options with these patients.

Thomas Mroz, MD: That's right. That's right.

Glen Stevens, DO, PhD: So, I come see you. I've progressed a little bit. We're going to maybe do something surgically. Is AI helping you or not helping you at this point? Or it's still in the "We're learning about it" stage?

Thomas Mroz, MD: No, we are starting to implement things here at the Cleveland Clinic. And so, one thing that we're implementing is a technology driven by a company called Health Data Analytics Institute (HDAI), which will preoperatively risk stratify our patients. Not according to neurological outcome after the surgery, but it'll risk stratify our patients based on a digital twinning technology using large Medicare databases. But essentially, we'll be able to risk stratify patients for morbidity, mortality, length of stay, discharge, disposition, and readmission, which is something fundamentally that spine surgery needs and actually every surgical service line needs.

But we internally have partnered with a third party to develop an AI platform to again do the things that in part HDAI does. But also we want to expand upon that and determine how neurologically patients are going to do, how they're going to be utilizing the healthcare system. Because we know high utilizers of the health system post-operatively. Also, it maps very well to patient-reported outcomes and also to cost so that we can better understand who should we and should we not operate upon. And if we operate on them, which is the best operation. We've got a lot of data and we've got a lot of surgeons doing spine surgery here. So it's just a ripe environment to create and use AI technologies to fine-tune our decision-making before surgery.

Glen Stevens, DO, PhD: Well, that's the secret sauce, right? Picking the right patient.

Thomas Mroz, MD: Absolutely.

Glen Stevens, DO, PhD: Picking the right surgery for the right patient.

Thomas Mroz, MD: Absolutely.

Glen Stevens, DO, PhD: And when not to do the surgery.

Thomas Mroz, MD: That's right.

Glen Stevens, DO, PhD: So, I know in brain tumor we use a lot of surgical navigation, and there's brain shifting with tumor surgeries and things. Do you use cervical navigation in cervical spine? Or you don't require it?

Thomas Mroz, MD: We typically, for the run-of-the-mill cases, we don't require it. For degenerative cases, typically not. For complex tumors, imaged guidance really does help. But where I think image guidance really helps… and this does have to do with myelopathy patients and patients who have coexisting deformities. When we see a patient for deformity, and there are different reasons why a patient could develop a cervical deformity, we have to not only correct the deformity but also relieve pressure on the spinal cord if it exists. And that's where I think image guidance within the cervical domain really helps make the surgery safer. Understanding where their vascular anatomy is, understanding the goals of the restructuring of the spine, and more smartly making the appropriate cuts in the bone to correct the deformity. We can't do that without the image guidance.

Glen Stevens, DO, PhD: So, if you're going to do my carpal tunnel, it's a little easier. You just put in, if it's my left hand, you just mark the left arm before you go in for surgery. A little more difficult when you're looking at something just in the midline, you're going to cut through the skin. How do you know you're at the correct level?

Thomas Mroz, MD: That's a great question. And we have evolved as a spine center over the past 20 years in terms of how we arrive at the right level. And right now, I think we have best-in-class across the entire country in our process to determine the right level. But what we do is in the cervical spine and in the lumbar spine, the staff surgeon is obviously involved and scrubbed in the surgery. And in the cervical spine, if it's from the front of the spine, we place a pin into the bone. If it's from the back of the spine, we put a non-modifiable clamp onto a bone in the back of the spine. We take an X-ray, and then that X-ray is then sent to a radiologist who's on standby to read the X-ray to confirm the level they call into the room. And then we arrive at a decision that we are at the appropriate level or not. And then we mark the spine with a blue marking pen and a high-speed burr, and then we communicate that level to the other members of the team. So it is a best-in-class, and it really does work well. It has minimized the chances of having the wrong-level surgery. But the risk is real, there's no question because the spinal levels when you're in surgery, particularly in a patient who's large, can be very, very challenging because the levels all look the same for the most part.

Glen Stevens, DO, PhD: So, I come see you for surgery and you ask me if I'm a smoker and I tell you I'm a smoker. And then I say, "Well, let's do the surgery next week." What do you say to me?

Thomas Mroz, MD: Well, it's a good question. We get asked it a lot and it has a lot of relevance to spine surgery. So in patients who smoke, they're at higher risk for having non-union. So if you're planning on doing a fusion from the front or a laminectomy infusion from the back, those patients at baseline are going to have a higher risk of a non-union. And what that means is that, if one or more levels don't fuse in the spine and the fusion occurs over three months, post-operatively three to six months, then there's about a 50% chance or so that they're going to be become symptomatic later on in the future. But we don't typically use that as a reason not to do surgery in patients who have progressive myelopathy because it's a very severe disorder that we want to make sure that the patients don't get worse neurologically.

But we can change our approach if the patient can't stop smoking. So coming in from the front of the spine or in the back of the spine, sometimes we'll take iliac crest bone graft using a patient's own bone. Because it has the patient's own bone cells and the molecules that promote bone formation, they will have a higher fusion rate. And sometimes we can overcome the risk of having a non-union in patients who smoke. But again, this also speaks to the benefits rather of having a laminoplasty, simply because laminoplasty does not involve a fusion. And so patients, unfortunately, we can say... I would never say to a patient "Well, continue to smoke." I always try to get them to stop smoking, but it's not going to meaningfully impair the success or failure of the surgery. With the exception the patients who do smoke also have a slightly higher risk of having an infection.

Glen Stevens, DO, PhD: And marijuana the same? Risk is nicotine?

Thomas Mroz, MD: Yeah, the risk is nicotine. So marijuana, I think the jury is still out in terms of its risk and relevance to having a non-union, whether it's orthopedic surgery or spine fusion.

Glen Stevens, DO, PhD: And I know you'd like to trust me, but you can't. So do you just check nicotine levels on everybody?

Thomas Mroz, MD: It varies from surgeon to surgeon. But I am more of the compulsive type of surgeons. I just want to understand everything that's going on. So I check. In all smokers, I will check nicotine levels before surgery.

Glen Stevens, DO, PhD: So, I come see you, and I tell you I was Googling the day before I came to see you, and I thought that stem cells would be good for me, or some type of artificial disc. What's the status on that?

Thomas Mroz, MD: Yeah, stem cells don't have a place in the cervical spine right now. Possibly in our lifetime, they will. I think there's some ground being gained by researchers in trying to determine which type of stem cells in what type of environment have merit. There's some really good research coming out with a stem cell treatment for lumbar degenerative disc disease that's entering into a randomized control trial in this nation, which could really change the landscape of spine surgery and spinal disorders.

With regard to disc replacement… Disc replacement can be used, and obviously this is a transition from single or two-level fusion in the anterior cervical spine. And this technology's been around for a couple of decades now, and sometimes we use it in patients who have a tall disc, relatively young, and patients who we want to avoid a fusion and we can use a total disc replacement. And the literature is actually quite good. I wouldn't say it's any better, per se, than a single or two-level fusion, but it's certainly no worse. And it can be used for patients who have cord compression and myelopathy in addition to patients who have a radicular component or just radiculopathy alone.

Glen Stevens, DO, PhD: What's new in the field? I mean, other than the things we've already discussed. Anything else new or you guys are looking at starting to do?

Thomas Mroz, MD: Sure. I think in the cervical spine, there are going to be two things. I think there are a couple of important studies that are being launched right now to determine the merits and limitations of laminoplasty versus laminectomy and fusion. A recent study came out that showed laminoplasty had benefit in terms of how patients perform with regard to number of different secondary outcomes and a recent randomized controlled trial of which Dr. Steinmetz here and were part of.

The other thing where I think cervical spine surgery will evolve over the next 10 years is AI. The two technologies that I mentioned before about preoperatively understanding who is the best surgical candidate and for what surgery should we apply to that particular patient. I mean, patient-specific care is going to really evolve in cervical spine surgery and in spine surgery in general. So it's going to be an exciting decade before us.

Glen Stevens, DO, PhD: Yeah, I guess if you fuse two levels, it'll help you better understand who's going to shift at the next level below, right?

Thomas Mroz, MD: That's right. That's right.

Glen Stevens, DO, PhD: And then you can have that discussion and decide. Maybe it makes sense to a three-level instead of a two-level.

Thomas Mroz, MD: That's right.

Glen Stevens, DO, PhD: As things go. So, final closing remarks for our audience?

Thomas Mroz, MD: No, I think this has been a wonderful discussion. I want to thank you for having me and you come as a very informed interviewer, and I appreciate it. These are really great, great, great questions.

Glen Stevens, DO, PhD: Tom, I really appreciate you taking the time to educate us a little bit more on this disorder and look forward to all the good things coming out of your department.

Thomas Mroz, MD: It's a real pleasure, Glen. Thank you

Closing: This concludes this episode of Neuro Pathways. You can find additional podcast episodes on our website, clevelandclinic.org/neuropodcast, or subscribe to the podcast on iTunes, Google Play, Spotify, or wherever you get your podcasts. And don't forget, you can access real-time updates from experts in Cleveland Clinic's Neurological Institute on our Consult QD website. That's @CleClinicMD, all one word. And thank you for listening.