A spine MRI report is a page of Latin, and most patients read it for the first time in the evening, alone. It contains discopathy, protrusion, perhaps extrusion, facet arthrosis, Modic changes, and at the end the sentence about a “pathological change”. Most people assume these words are a diagnosis. They are not. The report describes what the radiologist sees on the scan, and it does not say what hurts. This article goes through the most common terms, and for each one it says what the word means, and what it means for you.
A spine MRI shows the vertebrae, the discs, the ligaments and the nerves. The report is written by the radiologist, who sees the scan but usually does not see you. That is why a report is a description, not a verdict: it records what is visible, to what extent, and at which level.
From this follows the most important rule worth taking away from this article. A finding in the report acquires its meaning when it matches what you feel: on the same side, at the same level, and with a character that fits the complaint. Without that, the word remains a description.
There is one piece of data here that surprised many doctors as well. Pooled clinical trials show that in patients with back pain and no suspicion of a serious underlying condition, early imaging did not produce a better outcome than usual care without imaging: neither in pain nor in function. So a scan on its own does not heal, and it does not make us wiser in every situation. It is useful when there is a specific question for it to answer.
One technical note, because many people get stuck on this. The radiologist grades the morphology, that is the shape and the size, not your condition. When the report says “marked”, “advanced” or “severe”, it is describing the extent of what is seen, not how ill you are. The same goes for the word “pathological”: it means that this differs from a young, intact spine. Above the age of fifty almost every spine differs from that.
This article is not about one condition, it is about a situation. The situation is this:
If this is familiar, the sections that follow give exactly what you would be looking for at that moment: what the word means, and whether it has anything to do with what you feel.
The terms that describe the disc have an official, agreed meaning. The joint nomenclature recommendation of the international radiological and spine surgical societies was written precisely so that the same word means the same thing in every report. It is worth knowing that this recommendation keeps a separate category for findings whose significance is uncertain. In other words, the professional dictionary itself allows for a described sign not necessarily meaning trouble.
These are the words worth paying attention to, because matching the report against the complaint depends on them.
This is the most important section of the article, so I will support it with numbers as well.
A review pooling scans of people without complaints shows that the degenerative signs of the spine appear together with age, without pain as well. The proportions below refer to people who had no spinal complaint at all at the time of the scan:
| What the report says | At 20 | At 40 | At 60 | At 80 |
|---|---|---|---|---|
| Disc degeneration (discopathy) | 37% | 68% | 88% | 96% |
| Disc bulge | 30% | 50% | 69% | 84% |
| Protrusion | 29% | 33% | 38% | 43% |
| Facet joint degeneration | 4% | 18% | 50% | 83% |
| Spondylolisthesis | 3% | 8% | 23% | 50% |
It is worth reading this slowly. Two thirds of people in their forties show disc degeneration, half of them a bulge, and almost one in three a protrusion, while nothing hurts at all. By the age of sixty, facet joint degeneration affects every second person.
Two things follow from this, and both are practical.
The first: a finding on the report does not prove that it causes the pain. If the complaint does not fit it, then in all likelihood it is not the cause.
The second: if somebody over fifty has an MRI scan, we will almost certainly find something on it. This is not the moment of bad news, it is a question of the yardstick. Most degenerative signs are as much a part of passing decades as greying hair, with the difference that we have photographed this one and written it down in Latin.
What this does not mean: not that the report is pointless, and not that the pain is imagined. The pain is real. It is simply that its source is not always where the most striking image appears.
When the image and the complaint meet. Three things have to line up at the same time:
If these three coincide, and the physical examination points to the same place, then the report has become more than a description: it has become an explanation. That is when it makes sense to plan treatment around it.
It is important to add that even this does not automatically mean surgery is needed. Most disc herniations settle with non-surgical treatment. According to an analysis pooling follow-up scans of conservatively treated patients, about seventy percent of herniations retract on their own, and the resorption typically happens in the first six months of treatment. The form matters too, and in a way that runs against everyday logic:
| The word in the report | How often it resorbs |
|---|---|
| Sequestration (free fragment) | approx. 88% |
| Extrusion | approx. 67% |
| Protrusion | approx. 38% |
| Bulging | approx. 13% |
In other words, the form that sounds most dramatic on the report is the one that most often settles on its own. This reassures many patients, and it contradicts many a surgical instinct.
One limit has to be stated, however, because without it the figure above is misleading. Resorption is what shows on the image, but the measure of recovery is how you feel. It happens that the herniation is still there on the follow-up scan while you are already well, and the other way round too. That is why I do not tend to order a follow-up MRI just to “see whether it has gone”. Treatment is aimed at the complaint and at function, not at correcting the report. You can read more on separate pages about what a disc herniation on MRI means and about the tools of non-surgical treatment.
Two separate things are involved here: there are symptoms you must not wait with, and there are words in a report that call for prompt clarification.
Immediate specialist assessment is needed if:
And there are a few expressions in a report where you should not book for next month, but take the scan to a doctor within days:
I am not writing these words down so that anyone can diagnose themselves with them, but because they can also be buried in a report, between the lines, in cautious wording. If you see one, it is worth booking an appointment rather than searching further. There is a separate page on spinal tumours, and a separate guide on when a spinal complaint is urgent.
Where the report was frightening but the complaint was not. A patient of 52 with three weeks of back pain. The report shows multilevel discopathy, protrusion at two levels, facet arthrosis and a Schmorl's node. The pain stays in the back, it does not radiate into the leg, and the neurological examination is normal. The report is frighteningly long, but the findings listed are age-related signs, and none of them explains the character of the complaint. Targeted physiotherapy begins and the pain settles within weeks. Surgery never came up.
Where the more modest looking report was the point. A patient of 38 with right-sided pain running through the calf to the little toe, with a right-sided extrusion at the lowest level. The report is shorter than the previous patient's, but the side, the level and the character all match what the patient feels. Non-surgical treatment begins and the complaint eases substantially within two months. No follow-up scan is taken, because it would not influence the decision.
Where the report did not explain the complaint. A patient of 61 with left-sided leg pain, whose report describes narrowing of the right-sided exit canal. Surgery had been raised elsewhere. The side, however, does not match, and the examination does not support a nerve-related origin either. The right step here is not surgery but sorting out the diagnosis: looking for the source of the pain where it can actually be.
The difference between the three cases was not the severity of the report, but whether the described finding matched what the patient feels. These are typical courses, not promises. Individual outcomes may differ. You can read more cases here.
A good decision never comes from the report alone, but from the complaints, the physical examination and the report together. This information does not replace a medical examination. If in doubt, seek medical help, and immediately in the presence of urgent symptoms.
What is the difference between protrusion and extrusion?
The two are two degrees of the same process. In a protrusion the base of the bulge is wider than the bulge itself; in an extrusion it is the other way round: the material has squeezed through the annulus, so the protruding part is wider than its base. An extrusion presses on a nerve more often, and at the same time it also resorbs on its own more often.
If my report says “pathological”, am I ill?
In this context “pathological” means that the image seen differs from a young, intact spine. Above the age of fifty almost every spine differs from that. The radiologist grades the image, not your condition, and on its own the word says nothing about whether you need treatment.
Why does it hurt when there is barely anything on the report? And why does it not hurt when there is a lot?
Because the report and the complaint are two different things. A review pooling scans of people without complaints shows disc degeneration in two thirds of people in their forties, without pain. The reverse is true as well: pain can come from several sources, and some of them are not visible on a spine MRI.
Should I ask for a follow-up MRI to see whether the herniation has gone?
In most situations it is not worth it. Resorption is what shows on the image, but the measure of recovery is how you feel. A follow-up scan is warranted when its answer influences the decision, for example when surgery is being considered, or when the character of the complaint changes.
Can a disc herniation resolve on its own?
Often yes. According to an analysis pooling follow-up scans of conservatively treated patients, about seventy percent of herniations retract, typically in the first six months of treatment. Interestingly, the forms that sound most dramatic on the report are the ones that resorb most often.
My report says bulging. Is that a herniation?
Under the international nomenclature, no. A bulge is an even, broad-based change of shape of the disc, not a herniation. If your leg hurts and this is the only finding on your report, then it is unlikely to be the source of the pain. Together with other findings it may nevertheless contribute to pressure on a nerve.
What should I bring to the consultation?
The scan on a disc or digitally, not only the report text, your earlier reports, and a short note on how long the complaint has lasted, exactly where it is, what eases it and what makes it worse. If you have had spine surgery before, bring the operative report as well.
Bring your scan and your reports, we will go through them together, and I will give you a clear picture of what they mean and what your options are.
This article draws on the following professional sources: