437- The Link Between Spinal Instability and Degenerative Changes

Welcome to the Evidence Based Chiropractor where each week we deliver the latest chiropractic research and marketing strategies all in the time it takes to get to your office. Now here's your host, Dr. Jeff Langmaid.

Hello and welcome to the Evidence Based Chiropractor. I AM your host, Dr. Jeff Langmaid. On today's episode we have a fascinating brand new study that is all around spinal instability and its role in spinal degenerative conditions and changes. Fascinating study, massive amount of take home information. We'll dive into it and much more on today's episode. Before we get started, I'll say a few words about patient pilot by the smart chiropractor. If you're looking to increase your patient reactivations this year, who isn't? Staying top of mind is critical. Automation is the key to consistency. Consistency is the key to success. We help accomplish all of that. We provide you with hot lists for patient recalls. So your team is just not blindly calling upon date. We also consistently reach out to your patients, highlight who's clicking and much, much more. If you'd like to see how we help over 300 docs around the world generate more patient reactivations faster and easier than ever before, head over to and schedule a demo@thesmartchiropractor.com but as I said at the top, we're talking research today. Fascinating study. The study is actually about fusion surgery without decompression. But it is critical for us to understand the underpinnings of this study so we can head this off before these patients even get towards surgical intervention. So all awesome study. I'll drop a link to it in the show Notes the title is Defining role of Atlantoaxial and sub Axial spinal instability in the pathogenesis of Cervical Spinal degeneration. Experience with only fixation without any decompression as treatment in 374 cases over 10 years. So a very long study, 10 years, hundreds of patients and basically what they're looking at is when a patient has so I'll say it in my terms, they had patients go through fusion surgery, fixation surgery, without any decompression. That means without any laminotomy, laminectomy, foraminotomy, no disk ectomy, none of that. Just strictly the fusion to correct the instability. And they analyzed the results of that from that. Now you can reverse engineer. Well how are these playing together? Is this instability that leads to degenerative changes? Is it degenerative changes that leads to an instability? And with that I can tell you I learned a lot in this study and I hope you learn a few things as well. So for many, many moons, decades, we've looked at degenerative alterations of the disc really as it's a pathology that there could be age related items and, and that it's the degenerative change of the disc that ultimately begin the process of spinal degeneration. Well, about a decade and a half ago, the researchers that now have this study proposed an alternate concept that what they call vertical quote, unquote, spinal instability is actually the primary pathogenic issue in the initiation, development and progression of, of degenerative spinal disease. How did they come to this? They looked at the standing posture and they highlighted a few things I thought were really, really interesting. When we're in a standing posture, extension of the spine is the active muscle movement, while flexion is actually a passive movement. And the way or lens that they look at this through is we have a lot of posterior musculature, there's no question about that. We don't have as much anterior musculature specifically related to spinal movement. As a matter of fact, there's only a very small amount of muscles that work around the intervertebral disc andor the vertebral body. So they speculate that the intervertebral disc is actually the brain of spinal movement, while the brawn is the muscles. So acute or long standing, weakness of the muscles on the posterior chain of the neck can be due to a variety of causes. Right. We see these all day, every day. Injury, misuse, disuse, lack of proper care, not using them enough. And all of that can result in alterations. Changes influence the facet joints. And the facet joints are key here because when the facet articulation becomes unstable, that is when we see joint space start to become reduced and a listhesis take place that offset. So whether it is an enterolisthesis, whether it's a retrolisthesis forward or back, the facets have to be involved because they are a stabilizing component of the vertebral motion unit. So they go deeper in in this study, in and around the facets because of the differing orientations of the facets, oblique versus more horizontal in the cervical and lumbar spine and then in the cervical spine. This is sort of a unique case because basically they say there can be some false positives here. So vertebral facet instability can be missed sometimes on imaging. Now the really interesting point that they highlight is the secondary air quotes alterations. Now these secondary alterations are going to Sound like primary alterations to probably you, because they did to me. They highlight secondary alterations as reduction in disc space, reduction in inner facet spaces, bulging of the disc, buckling of the intervertebral ligaments, osteophyte formation, evidence of bone fusion. You and I, I look at images all the time and I view those as primary items when this study was saying they might be secondary to the instability. And that is a massive shift in how I have considered a spinal motor unit. These alterations of course can result in a plethora of stenosis. Right? You can end up with foraminal stenosis, you can end up with spinal stenosis, you can end up with lateral recess stenosis. Anytime you see facet space, crunch down disc space, decrease osteophyte formation. All of it can result in compressive pathology. And listhesis or movement is a really critical component of this. And we'll talk about why. When you think about a foraminal canal, it might not be something you think about every day in terms of the size of it, but they're roughly 6 to 8 millimeters in height and let's say 4 millimeters in width. I'm just roughing numbers, but it gives you an idea. Well, if you think about a 2 millimeter, let's say 1 to 2 millimeter offset, so somebody flexes forward and you see the anterior arch slide forward, a listhesis happens of 1 to 2 millimeters, that could be a 25 to 50% reduction in that foraminal canal size. Well, guess what? The nerve going out is gonna get crunched. That's when you're going to end up with a funk. I like to call it functional stenosis. Even though a disc might not be popping back into the space, your static images might look totally clean. I own a series of imaging centers where we focus on vertebral motion analysis for specifically this because static images tell a story, but movement based vertebral motion analysis tells the whole story. What can happen between neutral and full flexion? Neutral and full extension is a lot. And a 1-2 millimeter offset, which seems so minimal in a foraminal canal, could be up to a 50% reduction in size. That will cause that nerve to yell and scream. That can be a functional stenosis, specifically in the foraminal canals. We're talking right now, but the same thing can occur in the lateral recess or the central canal. So fascinating study. They looked at 374 patients over a 10 year period from 2012 to 2022. And each one of these Patients had single or multilevel spinal degenerative radiculopathy and or myelopathy. And all of them were treated surgically via effusion or fixation. 339 men, 35 women, age range was about 40 to about 80 with a mean age of 62 years old. So the aim for this surgery in every one of these cases was really simple spinal fixation fusion. That was the key. None of these individuals had decompression of the vertebral body, of the lamina, of the disc, of the ligament, of the osteophyte or of the posterior longitudinal ligament. So they literally went in and strictly fixated the joint, fused the joint, left everything else alone. And the goal was to see how do these patients do over time. The follow up period ranged from three months to 125 months. So they did have plenty of cases that went a really long time. And in this case all patients improved from their primary presenting clinical symptoms, which is really fascinating. And all patients had what they deemed clinical improvement as well. Meaning that, you know, there's subjective and objective. Essentially we can bracket that down to 92.2% of the patients were highly satisfied with their clinical outcome. And this is shocking. Out of 130 patients who were brought to the hospital in a wheelchair, 116 walked out independently. Absolutely fascinating. One one of these patients did need adjacent level anterior surgery afterward as well. So arthrodesis of the treated segment was considered successful. Basically the fixation of fusion. When the clinical improvement persisted, bone fusion could be observed across the facet articulation and there was no relative movement on dynamic imaging. So that's how they deemed success. So on visual impression, the extent of the reduction in the disc osteophyte ligament complex was minimal in in 31 cases, moderate in 41 cases, good in 62% of the cases and complete in 125 of the cases of 259 which they had these delayed images. So here is another fascinating fact. Partial or complete resorption of the herniated disc, prolapsed disc or extruded disc was observed in 24 out of 33 cases when the MRI was done. So six months after surgery, so hard stop right there. If they didn't touch the disc, but six months later the disc was healed, resorbed. However you wanna define that, what does that tell us? Tells us a couple different things and this is critical for us to know as chiropractors, conservative care specialists, movement based healthcare professionals. One is that the disc can heal Even in these are patients going for cervical fusion surgery. I mean, these are pretty extreme cases. This is not the everyday item. Right. Only a small fraction of people, thankfully go through a surgical intervention. When you get to that point, you're pretty far gone. So the fact that after fusing the segment, the disc was still able to heal after probably years, decades in many cases of injury, of maltreatment, of overload is awesome and fascinating. That tells us there's a lot of opportunity to heal when the situation is right. Two, it tells us that. In my mind, it tells me, I say, man, it sounds like I might not be. And I'm not telling patients to go in for fusion surgeries unless they absolutely need to. But if I can stabilize that region without surgery, what does that mean? It means building up muscle mass in the area, ensuring proper biomechanics, all of the things we do as chiropractors. That tells me that there's an opportunity there for the disc to heal itself. And that is powerful. We know it. But to see that six months down the road in overwhelming majority of cases that are surgical cases had disc improvement just due to this fixation or stability of the spinal segment is massive at absolutely massive. Especially because we know spinal radiculopathy, myelopathy is a big, big deal, particularly in the elderly and particularly as people age. And in this case, they found that a simple fixation, a simple fusion can provide a tremendous benefit for these patients. So they. One of their findings was, quote, our studies have identified intervertebral disc herniation to be a direct consequence of acute spinal instability, or that the instability of the spinal segments is a result of the disc herniation. Which came first, the chicken or the egg? The answer is it depends. And that is a fascinating finding because I've always thought of it in very linear terms and that might not be the case long term. So resorption of herniated disc or bulging disc material, unbuckling of the segments is something that absolutely can happen because as they're saying, it's actually secondary to the instability. And that is fascinating. So if we can get in there earlier on with patients, if we can address now a grossly unstable unit, a spinal unit, that's a surgical case, right? If it's grossly unstable. But if we're noticing that there is a listhesis on a film, if we're noticing that maybe there's not a listhesis, but the patient has functional radiculopathies, they're moving around and things hurt, they stay still. It doesn't feel as bad, the images look clean. That starts to become a very interesting case when we think about this might be not a disc issue. Obviously, if the MRI is clean, it's gonna tell us whether or not a disc is challenged. But that disc, even if challenged, can likely still heal if we're able to address the stability. And stability comes from a few different things, of course. One is it comes from ligaments which provide support. Two, it comes from musculature, which support movement. And the disc ties these items together, specifically when we're looking at vertebral body to vertebral body. So I don't look at this study saying in any stretch of the imagination, more patients need fixation or fusion. I look at this study and say, what if we're able to get in and address some of these instabilities earlier on in the process before it becomes a gross instability, but when it is earlier on, before it gets to the point of potentially needing a surgical intervention. If we can do that, if we can address some of the stabilization elements, we always say we want to see a balance of flexibility and strength that's tied. You know, these are tied together in terms of stability, right? Flexibility and strength. When you have adequate flexibility and adequate strength, your spine is going to be pretty healthy overall. However, when you have instability, probably due to a result of a lack of flexibility or too much flexibility, a lack of strength, maybe they're not such thing as too much strength, but muscle tone matters. This can result over time and instability. And then that cascade, and then keywords, then the cascade of additional challenges to the disc start to take place. So when you see a disc, when you see some of the things that we might think of as primary, look at them or think about them through the lens of them being potentially secondary to a spinal instability, not an instability that necessarily requires surgery, but an instability that potentially can still be head off before the patient gets there. How? By focusing back towards the beginning on strength and flexibility. And as you do that, and of course, proper biomechanics, getting in there and ensuring the joint can move freely and appropriately is key. You can't have great strength and great flexibility if your biomechanics at a segmental level are totally shot. But as we improve that with the adjustments we deliver, and then you look towards improving what I'll call the stability of that joint, it is highly likely that you will see many of the red flags. Red, maybe not red flags. Red herrings. Your spinal disc issues, your ligamental issues clean up over time. That was my take home message. If you had a different one, I would love to hear it. Jeff the evidencebasedchiropractor.com I I appreciate you tuning in each and every week. If you've not left a rating or review for this podcast, I would love it if you would take a moment and do so. And if you are serious about cervical spine assessments, you gotta check out neckcare neckcare.com I've been posting a ton of videos about this technology. Orey, their CEO came over to my house. We checked everything out. We did an interview. Awesome reliable assessments and exercises for the cervical spine. We're talking neuromusculoskeletal control, proprioception, range of motion, sensory motor integration. It is a technology driven objective assessment tool and if you geek out on that type of stuff, you're want to head over to neckcare.com I'll drop a link down below. Thank you so much for being a chiropractor. Have an awesome week in practice and I will talk to you soon.

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