Your "Bad" MRI Might Be Good News: What the Research Says About Disc Herniations Healing on Their Own
I have this conversation almost every week. A patient sits down across from me, pulls out their phone or a folded piece of paper, and shows me their MRI report. Somewhere in there is a word like "extrusion" or "sequestration," and I can watch their shoulders tense up as they wait for me to tell them how bad it is.
Here's the thing I want to walk through with you, because it's genuinely one of my favorite pieces of research to talk about: a lumbar disc herniation that looks more severe on imaging is often more likely to shrink or disappear on its own, not less. That sounds backwards. Let me explain why it's not.
What the research actually shows
There's a systematic review, published in 2015 in the journal Clinical Rehabilitation, that pulled together the available studies tracking herniated discs over time on repeat MRI, without surgery. When they broke the results down by the type of herniation, here's what they found.
Simple disc bulges regressed on follow-up imaging about 13% of the time. Disc protrusions regressed about 41% of the time. Disc extrusions, which sound scarier, regressed about 70% of the time. And sequestered disc herniations, the most severe classification on an MRI report, where a fragment of disc material has actually broken free, regressed a striking 96% of the time.
Complete resolution, the herniation essentially disappearing on later imaging, happened in 43% of sequestrations and 15% of extrusions.
I want you to sit with that for a second, because it's the opposite of what most people assume when they read their own report: the more severe the disc herniation looked on the scan, the more likely it was to shrink or resolve completely without any procedure at all.
Why does a more severe herniation heal faster?
This comes down to your immune system, and once you understand it, it actually makes a lot of sense. When a piece of disc material herniates far enough to break through the outer wall of the disc, that material gets exposed to your bloodstream in a way it normally never is. Your body recognizes it as tissue that doesn't belong, and immune cells move in to break it down and clear it out, the same basic cleanup process your body runs anywhere else after an injury.
A larger, more severe herniation, like an extrusion or a sequestration, actually gives your immune system a bigger, more accessible target. A small disc bulge often stays tucked inside the disc's outer layers, where your body's repair processes have a much harder time reaching it. That's a big part of why the "worse" findings on paper often resolve faster and more completely than the milder ones.
Why I think this matters more than the report itself
So much of the fear around back pain gets built entirely on what a scan shows, instead of what your body is actually able to do. I've seen patients handed an MRI report, told the findings were "significant," and steered toward injections or a surgical consult largely because the image looked alarming, not because their actual symptoms or function demanded it.
Imaging findings and pain simply don't correlate as tightly as most people assume. There are plenty of people walking around with zero back pain who have disc bulges and even herniations on imaging they don't know exist. And there are plenty of people with genuinely severe-looking disc herniations who go on to improve significantly with time and the right conservative care, in part because of the exact mechanism I just described.
To be clear, this doesn't mean imaging is useless or that severe symptoms should ever be brushed off. Red flag symptoms, like progressive weakness, loss of bowel or bladder control, or pain that isn't responding to anything at all, always need to be evaluated quickly. But for the large majority of disc-related low back pain and sciatica, the size or severity of the finding on your report is not a life sentence, and it's not automatically a reason to jump straight to the most invasive option on the table.
What we actually focus on with our patients
Instead of treating the MRI as the whole story, we focus on what your body can currently tolerate, what's actually driving your specific symptoms, and how to rebuild your capacity while your body does what it's already built to do: heal. That means tracking your progress and your function, not just your scan, and building a plan around movement and capacity rather than a picture and fear.
If you're sitting on an MRI report full of intimidating words and no clear plan for what to do next, that report doesn't have to be the end of the conversation. In my experience, it's usually just the beginning of understanding what your body actually needs.
Got an MRI report that's got you worried about a herniated disc? Book a discovery visit at Momentum Spine and Sport in Orange City, and let's talk through what it actually means for you.
— Dr. Cory Sellers
Source: Chiu CC, Chuang TY, Chang KH, Wu CH, Lin PW, Hsu WY. The probability of spontaneous regression of lumbar herniated disc: a systematic review. Clinical Rehabilitation. 2015.
