|Thanks to the graciousness of a recent coaching session client, I can present a classic example of symptomatic degenerative lumbar stenosis complicated by disc protrusion and classic isolated disc resorption (I am in the process of designing a webpage on this fairly common condition, so stay tuned). Please enjoy this tutorial complements of a client who shall remain nameless.|
1) lateral view (x-ray) of the lumbar spine.
*Note the thin disc spaces at L4/5 and L5/S1; note the traction spur (red arrow) extending into the neural foramen.
2 ) overhead view of the L5/S1 disc.
TS= thecal sac; DRG = ; dorsal root ganglia
warm = traversing S1 nerve roots;
red circle = facet joint;
curved yellow lines = back of the bulging disc.
* no contact between disc and S1 nerve roots or thecal sac.
|3 ) one slice up shows the inferior aspect of the L5 vertebral body. Everything is completely normal ; just a nice specimen to show anatomy.|
4) the region between the yellow lines at L5/S1 is called the neuroforamina (aka: intervertebral foramen or IVF). The region between the pink lines is called the lateral recess.
This is a beautiful example of where the patient has a lot of "wiggle room" as these canals are very large and allow the exiting L5 nerve root plenty of space without compression.
5) here we have a small central disc protrusion (yellow line) which is compressing the anterior thecal sac (TS) because the diameter of the central canal has been greatly reduced (i.e. central stenosis) secondary to hypertrophy of the facet joints (purple) and ligamentum flavum (yellow). note how compressed lateral recess, and neuroforamina are from this degenerative process.
This stenosis would be classified as moderate and has resulted in lateral recess and neuroforaminal stenosis.
6) this is a completely normal L3 disc. note that you can still differentiate the nucleus pulposus from the annulus fibrosus.
*there is some hyper intensity (white color) within both facet joints (red curved lines) as well as what appears to be a facet ganglion cyst (red arrow). The fluid in the facet joint, which might be normal artifact, could be an indication of inflammation which of course could cause back pain and perhaps some pain into the thighs.
7) again we see the problem at the L4/L5 level, as the central disc herniation and degenerative posterior arch changes (i.e., the ligamentum flavum thickening and facet joint hypertrophy) have created a stenotic condition.
*When we see endplate changes (orange and the whiteness in the bone = Modic changes) with rat bite erosion of the endplate and loss of disc height, this equals a condition called isolated disc resorption which is associated with chronic pain.
T1 images indicate these Modic changes are classified as Type I (more rare) which can be indicative of an acute process (i.e., bone marrow edema).
|8) same MRI just looking at a slice more laterally. Here we can see a relatively large endplate defect (a Schmorl's node) in the inferior endplate of L4. These are also associated with pain on a relative scale (i.e., the bigger the Schmorl's node, the more related to pain it is). You can also see the central herniation (orange). If you look close, I have also put a purple line depicting the traversing nerve roots as they hang in the thecal sac|
History: Rowing Team, kayac, history. then injured lifting book shelf - 2007. Pain is 100% lower back - used to have right let pain but not very strong (did have some weakness). Prolonged sitting > two hours. Currently flared up from a hiking trp and frustrated by the fact she cannot do the things she once used to do. Oswestry is in the mid-20s.
I just want to say thank you for letting me use your page and images for my website (of course no identifying information will be used) and if you have any questions that you forgot to ask, please feel free to e-mail me I would be more than happy to answer.
And just a quick recap: you are more likely than not suffering from L4/L5 central, lateral recess, and neural foraminal stenosis (moderate in nature) which is complicated by a small central disc protrusion. We know there is a small traction spur possibly further complicating the problem (I would guess its in the right neural foramen). You also have what we call isolated disc resorption (early stages) with associated disc space narrowing, endplate corrosion, Modic changes, and Schmorl's node.
Given your Oswestry, you're obviously not a candidate for fusion at this time and should continue with your routine of swimming and walking – although I would be careful of the yoga because you have not had any flexion / extension / lateral flexion radiographs to ensure stability (this might be a good study to get the next time you see the doctor).
I wish you the best of luck with your back!