What is Lumbar Degenerative Spondylolisthesis - Part 1

Welcome to Spine Guy, I'm Dr. Brian Sue, a fellowship trained spine surgeon, we're in California, The Spine Boys, a channel dedicated to simplifying the complex spine so patients understand today we'll be talking about

degenerative

lumbar

spondylolisthesis

, which are three really important words. or at least one big word

spondylolisthesis

and I promise that by the end of the video it will be totally clear to you. I'll be posting new videos weekly, so hit the subscribe button to watch them as they appear. The word

lumbar

means lower back. which is this, there's the back, there's the belly,

degenerative

means something that happens over time as people age, everyone suffers from degeneration in the spine.

If someone over 50 had an MRI or X-ray, almost 75 percent would have degenerative disc arthritis. etc Spondylolysis is a fancy word for sliding, it literally means one bone slides in front of another, so this is a normal lumbar spine, there's the back, there's the buttock, there's the abdomen, this is the sacrum, which is the big bone in the lower lumbar 5, which is l5 l4 l3 all bones are supposed to stay nice and aligned in every position, so when a patient extends back or flexes forward, they are supposed to All these bones should remain stacked on top of each other like building blocks, there is not supposed to be any kind of abnormality. movement a spondylolisthesis means abnormal sliding which means

what

can happen over time is that one bone can slide in front of another for example I have created it in this model but this is bone l4 and that is bone l5 and

what

can What happens is that the l4 bone and the entire spine above it can shift forward and that usually happens because the little joint in the back called the facet joint over time can develop arthritis and dysfunction.

This abnormal alteration of the biomechanics of the spine occurs both at the level of the disc and at the level of the facets and the spine does not move as a unit, this

part

of the spine is falling forward. Degenerative spondylolisthesis is best diagnosed with x-rays because on x-rays you can see the bones slipping and sliding as it progresses. I can imagine that if the bones slip and slide, what can happen is that the nerves in your back can start to get pinched and you can start to develop pain in your buttocks and legs because the nerves go to your buttocks and legs. legs, and the sciatic nerve begins to be compressed. the actual displacement of the bone, the image on the left shows an absolutely normal spine, this is the l4 alpha bone which says sacrum, that's why we call it s1, so the bone is a square and this is the back of that bone , the back of that bone on On the back of that bone, I've drawn a line on the back of each bone.

You can see that these lines actually line up perfectly. This is someone who has spondylolisthesis, so there's l3, l4, l5, and s1, and if you were to look at the back of each bone you'll see that the back of l3 lines up with the back of l4, but at l405 there's a little bit. step or a ladder. I've drawn lines to show you how these bones line up. These bones align, but between l4 and l5 there is that step now remember that the bones are named by numbers for example l4 and l5 the disc is named after the bones of the sandwiches this is the l45 disc because it is the disc between the bones l4 and l5 and that is the displacement that is measured spondylolisthesis is classified in two different ways: the first is a classification system in which we classify it from one to four, with four being the most severe.

The system begins by dividing the bottom bone, which is the l5 bone, into quarters or 25 percent, 50 and 75 percent, then look at the amount of slippage of one bone relative to the next for a grade one degenerative spondylolisthesis, the slippage It is less than 25 of one bone with respect to the next for a grade two between 25 and 50 and a grade 3 between 50 and 75 percent and a grade four, which is the most serious at more than 75 percent. The second way to describe degenerative spondylolisthesis is by simply measuring the number of millimeters that one bone slides against another. Here you will see that we have marked the posterior

part

of the l4 bone and the posterior part of the l5 bone and we simply measured the displacement which is 10 millimeters here, so you can see this sliding described simply as 10 millimeters of spondylolisthesis of l4 on top of l5 if You want to rate this slide like we did before.

You can see that the 10 millimeter displacement falls between the 25 and 50 line, which would be described as a grade 2 spondylolisthesis in our world, which is the world of surgeons, there is grade one, grade two, grade three, grade four , grade one is mild, grade two. it's a little bit more three and four are serious, it really has to do with how much translation there is and you can talk to your doctor about the degree of spondylolisthesis that you have, in addition to the x-ray MRI, it's very important as well because the MRI not only shows us the slip but also shows us how much the nerve is compressed by that slip.

I'm going to show you the MRI of a patient who has an L45 spondylolisthesis and the reason I show L45 is because it is by far the most common level to have a degenerative spondylolisthesis. Here's a good example from the MRI, so this is the lateral view which is called the sagittal view, so there's the back, the buttocks, the abdomen, these are the l4 bone, there's the l5 bone and again. The back of the L3 bone and the L4 bone were drawn and there you see that small step outside of L5 and S1. Interestingly, this is the same MRI of the patient you saw earlier on an x-ray.

This is the cross section view, so this is laying down looking from the bottom up, looking through the spine, this is the opening where the nerves should be and this is a cross section of the four five and I encourage you to Watch a spine video on how to read a lumbar MRI if you do. you'll understand this, but this is the disc at l45 and this type of triangle here is where the nerve should be, this is what is called facet joints and the facet joints are the joints that connect the bones in the back, so this would be the l4l5 facet and obviously if there is a lot of instability or abnormal movement the facet joints really start to open up so when you look at a cross section of the facet joints you will see that there is a lot of fluid or really abnormal opening in the joints facets the most important thing to notice here is the amount of stenosis stenosis is a fancy word for narrowing this area or where the nerves are pinched and you can see that it corresponds here with this sand bending and pinching of the nerves, really what is suppose.

This entire area is supposed to be open, but you can see that it is closed in this very narrow space. Spondylolisthesis is a dynamic problem, meaning the bones slide and slide and slide and slide depending on how much. severity exists, it is very important to get what is called a flexion and extension x-ray or at least a standing x-ray because that shows how much instability there is when you are standing, patients with spondylolisthesis often feel very good where they are lying down. flat because that spondylolisthesis when there is no gravity when you are lying down has reduced and is level, whereas when you stand up and there is gravity, the spine suddenly slides, so here you have an upright x-ray, this is a patient standing like this, you can look, there is a step between l4 and l5, there is that kind of staircase, this is the MRI of the same patient.

What's super interesting is that the back of l4 is almost completely aligned with the back of l5, so one would say from looking at this MRI that yes, there's a little bit of narrowing here, but there's actually not much instability. not many steps, so how can it be the same patient? The reason is that the same patient is because an MRI is performed when you are lying down and there is no gravity. Once the patient stands up and there is gravity, the spine can be seen to suddenly slide, so simply looking at an MRI is not enough for a degenerative spondylolisthesis.

You really have to get that standing gravity view to see how much the spine slides. We can make a judgment about treatment and diagnosis if you want to go a step further. I always get what's called a forward flexion x-ray, so this is a normal standing x-ray, like that, with the patient on their side. This is a forward bend. x-ray, which is what we tell the patient to keep their knees straight, bend and try to touch their toes as best we can, so on a forward bending x-ray there's the back, there's the buttock, there's the abdomen and now when you look at the step you can actually see how the back of the four is, there is the back of the l5 and there is a significant translation from the l4 bone to the l5 bone, why is that so important?

That is important because particularly surgical treatment of a degenerative disease. Spondylolisthesis really has to do with how mobile you are, meaning how much you shift back and forth with gravity and reflection, so if you are being evaluated for degenerative spondylolisthesis, you really want to insist on at least one x-ray. , if not good flexion and extension. X-ray, what are the symptoms of degenerative spondylolisthesis? It is usually back pain and leg pain, so what does back pain come from? Back pain is due to instability secondary to changes in the facet joint. This facet joint becomes arthritic as there is more instability and more abnormal sliding there is more arthritis and it's kind of a top down effect where you get increasing amounts of arthritis in the facet joint and the results can sometimes be degeneration in disc and disc degeneration also causes back pain, so just abnormal arthritis instability, disc problems can cause back pain, most patients, frankly, can live with back pain, which can't stand is the pain in the buttocks and legs that occurs as a result of spondylolisthesis.

Spondylolisthesis, as you saw, can cause stenosis that narrows as there is abnormal movement. What happens is that the nerve becomes compressed where the instability is, and in fact, the more instability it is, the more compression there is. The compression of the nerve causes pain in the buttocks and legs, sciatica, leg cramps, needles, numbness, and patients do not like to walk long distances. Because while walking the bone slides and compresses the nerve, they often have to sit or lie down to feel better and weakness in the legs, ankles and quads can also be a very common symptom.

Hopefully you've learned a little bit about what a degenerative spondylolisthesis is not the worst spondylolisthesis is not that confusing and in the next episode we'll talk about non-surgical treatments for degenerative spondylolisthesis. Thanks for watching, don't forget to hit the like button and leave any questions or comments in the comment box below, feel free to let me know what videos you would like to see in the future.