Author: Jake Neil, Chiropractor, Innate Health Chiropractic, Exeter
A lumbar MRI report describes what the radiologist can see in your lower back. It does not, by itself, tell you what is causing your pain or which treatment you need. Terms such as disc bulge, herniation and stenosis describe different findings. Their importance depends on your symptoms, physical examination and whether the location of the finding fits the pattern of your pain or weakness.
If you have opened your MRI report and found several unfamiliar terms, it is easy to focus on the most alarming phrase. Here is a practical guide to what common terms usually mean and what to ask the clinician who reviews your scan.
What is a lumbar MRI looking at?
The lumbar spine is the lower part of your back. An MRI can show the discs between the vertebrae, the spaces through which nerves travel and other soft tissues. The radiologist describes visible findings at each spinal level, usually labelled L1–L2 through L5–S1.
An MRI is useful when its result can change a clinical decision. It is not routinely needed for every episode of back pain or sciatica. If you are still deciding whether a scan is appropriate, read our guide to when an MRI for sciatica may help.
Disc bulge: what does it mean?
A disc bulge means part of the disc extends beyond its usual boundary. The report may describe where it bulges and whether it narrows a nearby space. A bulge can be present without causing symptoms; the word alone does not tell you that a nerve is trapped.
Its relevance increases if the report describes contact with or pressure on a nerve that fits your leg symptoms and examination. Even then, the clinician needs to consider the full picture rather than assuming every visible bulge is the source of pain.
Disc protrusion or herniation: is that a slipped disc?
A disc herniation describes disc material pushing further out from its normal position. Protrusion and extrusion are more specific terms a radiologist may use to describe its shape. “Slipped disc” is a common expression, although the whole disc has not literally slipped out of place.
A herniation may irritate a nearby nerve root and contribute to pain, tingling or numbness travelling down the leg. Some herniations cause few or no symptoms. The report matters most when the affected side and nerve level make sense alongside your symptoms and examination.
If you want to understand the care options, see our herniated disc treatment page.
What does spinal stenosis mean?
Stenosis means narrowing. In a lumbar MRI report, this may describe the central spinal canal, a smaller passage beside it called the lateral recess, or the opening through which a nerve exits, called a foramen.
Lumbar spinal stenosis can be associated with leg pain, heaviness, numbness or weakness, often brought on by standing or walking and eased by sitting or leaning forward. The pattern varies. Some people have narrowing on a scan without corresponding symptoms, so the degree of narrowing is not a diagnosis on its own.
What do “nerve root contact” and “nerve root compression” mean?
These phrases describe a visible relationship between a disc or narrowed space and a nerve root. Contact means the structures appear to touch. Compression suggests pressure or displacement. Neither phrase measures how much pain you feel.
For example, if your symptoms are predominantly in your right leg, a left-sided finding may be less convincing as the explanation. Your clinician will also consider which movements are weak, where sensation has changed and whether the examination supports the suggested nerve level. People can have more than one finding, and the report may not provide a single clear answer.
What about “degenerative changes” or “disc desiccation”?
Degenerative changes is a broad term for changes in spinal structures that become more common with age. Disc desiccation means a disc has less water content and may look darker on particular MRI images. These words can sound severe, but they do not mean your spine is crumbling or that pain will inevitably worsen.
A published systematic review found that degenerative MRI findings are common even among people without back pain. That does not mean your symptoms are imaginary or that every finding is irrelevant. It means the scan must be interpreted in the context of your symptoms.
Does the most severe finding on the report explain my pain?
Not necessarily. A useful review asks:
1. Do the symptoms and scan point to the same side and level?
2. Is there a change in strength, sensation or reflexes that fits?
3. Has the problem been improving, stable or progressing?
4. Would this finding change the next treatment or referral decision?
The answers can also change over time. If you notice new or increasing weakness, seek prompt clinical advice even if a previous report described only a mild change.
Does a disc bulge or stenosis mean I need surgery?
No. Many people with disc-related sciatica improve without an operation. Others need a specialist opinion because symptoms remain disabling, neurological function is changing, or non-surgical care has not helped. The appropriate plan depends on the person, not on one line of an MRI report.
At Innate Health Chiropractic in Exeter, we consider your history, examination and any available imaging when discussing options for sciatica or disc-related pain. These may include conservative care, an assessment of whether IDD spinal decompression is appropriate, or medical referral. A scan finding alone does not establish suitability for IDD.Check this paragraph against the clinic’s current imaging policy before publishing.
When should you seek urgent help?
If you have back or leg pain with new numbness around the genitals or bottom, new difficulty passing urine or loss of bladder or bowel control, sciatica on both sides, or severe or worsening weakness or numbness in both legs, go to A&E or call 999. Do not wait for a routine MRI review or a clinic appointment. Read the NHS emergency advice for sciatica.
The next step if your report is confusing
Bring the written report and, if available, the MRI images to a qualified clinician who can examine you and explain which findings are relevant. Ask: “Which finding matches my symptoms, and what does it change about my care?”
If you are experiencing persistent back or leg symptoms in Exeter, book an assessment to discuss the appropriate next step.
Frequently asked questions
Can a lumbar MRI show sciatica?
MRI can show findings such as a disc herniation or narrowing near a nerve root. Sciatica is assessed using the symptom pattern and examination; the scan may help identify a cause but does not diagnose your pain in isolation.
Is a disc bulge the same as a herniation?
They are related but different descriptions of how disc tissue extends beyond its usual boundary. The precise wording matters less to your care than the location, symptoms and examination findings.
What does L4–L5 or L5–S1 mean on my report?
These labels identify levels in the lower spine. They tell you where a finding is seen, not automatically which nerve is involved or what treatment you need.
If my MRI says “mild”, why does it hurt so much?
Scan wording describes visible anatomy, not a pain score. Pain can be influenced by nerve irritation and other factors that do not map neatly to a radiologist’s severity label. Your symptoms still deserve assessment.
Sources cited:
● NICE NG59: imaging when results may change management
● Sherwood Forest Hospitals NHS: lumbar spinal stenosis
● Brinjikji et al., AJNR 2015: degenerative MRI findings in people without symptoms
● NHS: sciatica and emergency warning signs
Authored by Jake Neil, chiropractor at Innate Health Chiropractic- Exeter. Jake graduated from the Anglo European College of Chiropractic in 2013 and has been practicing in Exeter since 2021. He is also trained to operate the specialist Accu-Spina system using IDD non-surgical spinal decompression, currently the only one in Devon and Cornwall.
Written 23 September 2026