How to Read Your MRI Report — A Patient's Guide to Spine Scans
Spine CareSainikpuri, Hyderabad10 min read
Most patients receive their MRI report without a proper explanation of what it means for their symptoms and treatment.
You went for an MRI. You waited days for the report. You received a document full of terms like "posterior disc bulge at L4-L5 with thecal sac indentation and right-sided foraminal narrowing causing moderate neural compromise" — and were sent home without a clear explanation of what any of it means.
This is one of the most common patient experiences in spine care across Hyderabad and India. Radiologists produce technically accurate reports written for doctors — not patients. When those reports land in the hands of a worried patient with a back problem who has not yet seen a specialist, the result is either unnecessary panic or inappropriate reassurance, depending on which parts of the report they focus on.
This guide explains the terminology you are most likely to find in a spine MRI report — in plain language, without dismissing the findings or exaggerating them. At the end, it explains the one thing that matters more than any term in the report.
First — The Most Important Thing About Any MRI Report
Before explaining what the terms mean, there is something more important to understand: an MRI report is not a diagnosis. It is a description of what the radiologist sees in the images. It does not tell you whether those findings are causing your pain. It does not tell you what treatment you need. And it does not tell you how serious your condition is.
An MRI report requires clinical correlation — a spine specialist must match what the imaging shows with what the physical examination finds. A finding that looks alarming on paper may have no clinical relevance. A finding described as mild may be producing severe symptoms. The report is half the picture. The clinical examination is the other half.
With that context in place — here is what the terms mean.
The Complete MRI Report Terminology Decoder
Spine MRI Terms — Plain Language
Disc bulge / Bulging disc
The disc has extended beyond its normal boundary but the outer ring is still intact. Very common finding — present in a large proportion of adults over 40 even without symptoms. Significance depends on whether it is touching or pressing on a nerve.
Low — very common
Disc herniation / Herniated disc
Disc material has pushed through or ruptured the outer ring. More significant than a bulge. Can cause nerve compression producing pain, numbness, or weakness in the arm or leg depending on the level.
Moderate — depends on nerve involvement
Disc protrusion
A focal herniation where disc material projects outward from the disc boundary. Specifically means the base of the protrusion is wider than the protruding portion itself.
Moderate — requires clinical assessment
Disc extrusion
The inner disc material has broken completely through the outer ring. The protruding portion is wider than the base — or the material is clearly separate from the disc space. More significant than protrusion. Often causes significant nerve compression.
Higher — specialist evaluation needed
Thecal sac indentation
The thecal sac is the protective dural covering around the spinal cord and nerve roots — like a protective sleeve. Indentation means the disc or bone spur is pressing against this covering. It is touching the sleeve — not necessarily compressing the nerves inside it. Severity depends on the degree.
Moderate — important but not always symptomatic
Nerve root compression / Neural compression
The disc or bone is directly pressing on a nerve root. This is clinically significant. When present, it explains why you may be having leg or arm pain, numbness, or weakness. The specific nerve root compressed determines where in the limb symptoms appear.
Significant — clinical assessment essential
Foraminal narrowing / Foraminal stenosis
The foramen is the opening in the vertebra through which the nerve root exits the spinal canal. Narrowing of this opening compresses the nerve as it exits. Causes arm or leg pain and can produce weakness and numbness in specific distributions.
Moderate — severity depends on degree
Spinal canal stenosis / Central canal narrowing
The spinal canal (the tunnel the spinal cord and nerve roots run through) is narrowed. Mild narrowing is common and may be asymptomatic. Significant narrowing can compress the spinal cord or multiple nerve roots — causing symptoms in both legs or difficulty walking.
Important — degree determines significance
Disc desiccation
The disc has lost water content. Discs are mostly water when healthy — desiccation indicates degeneration has begun. The disc appears darker than normal on MRI. Common from age 30 onwards. Not automatically symptomatic.
Early degeneration — very common
Loss of disc height / Disc space narrowing
The disc is thinner than normal — it has lost height as part of the degeneration process. This brings the vertebrae closer together and can cause bone-on-bone contact. Often associated with pain and stiffness.
Moderate — common in adults over 45
Osteophytes / Bone spurs
Bony projections that grow at the edges of vertebrae in response to disc degeneration. The body tries to stabilise a degenerated segment by adding bone. Osteophytes can narrow the spinal canal or foramina and press on nerves.
Moderate — depends on location and size
Spondylosis
A general term for degenerative changes in the spine — includes disc degeneration, osteophyte formation, and facet joint changes. Cervical spondylosis refers to these changes in the neck. Lumbar spondylosis refers to the lower back.
Common — age-related finding
Facet joint arthropathy / Facet hypertrophy
The small joints at the back of each vertebra (facet joints) have developed arthritic changes or have enlarged. Can contribute to back pain, particularly with extension (bending backwards), and can narrow the foramina where nerves exit.
Moderate — common in older adults
Diffuse disc bulge
The disc bulges symmetrically in all directions rather than in one specific direction. Generally less likely to compress a specific nerve root than a focal bulge. Common finding with disc degeneration.
Common — usually less concerning
Posterior disc bulge / Posterolateral disc bulge
The disc has bulged backward (posterior) or backward and to one side (posterolateral). Posterior bulges point toward the spinal canal. Posterolateral bulges point toward the nerve exit channels on one side — more likely to compress a specific nerve root.
Important direction — assess for nerve involvement
Cord compression / Myelopathy changes
The spinal cord itself — not just a nerve root — is being compressed. Signal changes in the cord on MRI suggest the cord tissue is being affected. This is a serious finding that typically requires urgent specialist evaluation and may need surgical decompression.
Urgent — specialist evaluation without delay
Mild / Moderate / Severe
Describes the degree of canal or nerve compression in the radiologist's assessment. Important caveat: severity on MRI does not reliably predict symptom severity. Many patients with "severe" MRI findings have mild symptoms. Some with "mild" findings have significant pain. Clinical correlation is essential.
Relative — must be interpreted clinically
An MRI shows structure — the clinical examination determines whether that structure is causing your symptoms.
Understanding Spinal Levels — What L4-L5, L5-S1, C5-C6 Mean
MRI reports reference spinal levels using letters and numbers. Understanding this system helps you locate where in the spine the finding is.
C
Cervical — Neck
C1 through C7. Problems here can cause neck pain, arm pain, hand symptoms. C5-C6 and C6-C7 most commonly affected.
T
Thoracic — Mid-Back
T1 through T12. Less commonly affected by disc problems. Problems here can cause mid-back pain and rib-level symptoms.
L
Lumbar — Lower Back
L1 through L5. Most common site of disc problems. Issues here cause back pain and leg symptoms (sciatica). L4-L5 and L5-S1 most frequently affected.
S
Sacral
S1 through S5. S1 is involved in L5-S1 disc problems — causing symptoms down the back of the leg to the heel.
What "Mild, Moderate, Severe" Actually Means — And Why It Is Not the Whole Story
Mild
Disc or bone spur touching surrounding structures — not causing significant compression. Often asymptomatic.
Moderate
Meaningful compression present. Symptoms likely but not guaranteed. Clinical examination essential.
Severe
Significant compression. Symptoms usually present. Urgent clinical assessment warranted.
The critical point: MRI severity and symptom severity frequently do not match. Research consistently shows that a large proportion of adults over 50 have disc bulges, herniations, and even moderate foraminal narrowing on MRI without any back pain or leg symptoms at all. Conversely, some patients with severe back and leg pain have relatively modest MRI findings.
This is why the radiologist's report cannot tell you whether you need surgery, physiotherapy, or nothing at all. Only a spine specialist who has examined you — assessed your reflexes, muscle strength, sensation, and movement — can interpret the MRI findings in the context of your actual clinical picture.
Red Flag Findings That Need Prompt Evaluation
See a Spine Specialist Promptly If Your Report Mentions
Cord compression or myelopathy — particularly with signal changes in the cord
Severe canal stenosis at multiple levels
Disc extrusion with significant nerve root compression
Cauda equina involvement — multiple nerve roots at the lower lumbar levels
Any finding with associated symptoms of weakness in legs, walking difficulty, or bladder changes
These findings warrant evaluation without delay. Call Pure Ortho Hospitals, Sainikpuri: 8686868208
What Happens at a Spine Consultation at Pure Ortho Hospitals, Sainikpuri
When you bring your MRI report to a spine specialist at Pure Ortho Hospitals, the report is reviewed alongside your examination — not instead of it. The consultation answers the three questions that the report alone cannot answer:
Three questions only a clinical consultation can answer
Is this finding causing your symptoms? The examination checks whether the nerve or level identified in the report corresponds to your actual symptom pattern.
How serious is your specific situation? Not the MRI severity grade — your functional status, how it is affecting your life, whether it is progressing.
What does your treatment path look like? Conservative, injection, surgery — and which specifically for your case, your age, your activity level, and your goals.
Meet the Spine Team at Pure Ortho Hospitals
Orthopaedic Surgeon
Dr. G. Uday Sekhar Reddy
MBBS, MS Ortho, MCh Ortho
Spine Surgeon
Dr. Sai Krishna C.S
MS Ortho (University Gold Medalist), DNB Ortho, Fellowship in Spine Surgery
Sports Medicine & Joint
Dr. V.S. Abhilash Kumar S
MBBS, MS Ortho, FIJR, FISS (S.Korea, USA) — Clinical Director
Physiotherapy
Dr. L. Sreeram
MPT (Ortho), FDOR, MIAP
Physiotherapy
Dr. L. Sri Dharani
BPT, MIAP, PTOTA (Canada)
Frequently Asked Questions
What does disc bulge mean on an MRI report?
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A disc bulge means the disc has extended beyond its normal boundary but the outer ring is still intact. It is a very common finding — present in many adults over 40 even without symptoms. Whether it matters depends on whether it is pressing on a nerve, which requires clinical assessment.
What does thecal sac indentation mean?
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The thecal sac is the protective covering around the spinal cord and nerve roots. Indentation means the disc or bone is pressing against this covering. It is a significant finding but does not automatically mean nerves are being compressed — the degree of indentation and your clinical symptoms determine the significance.
What is the difference between disc bulge and herniation?
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In a bulge, the outer disc ring is intact. In a herniation, disc material has pushed through the outer ring. Herniations are generally more significant — more likely to cause nerve compression — but both can be symptomatic or symptomless depending on what they are pressing on.
Should I be worried if my MRI says "moderate" or "severe"?
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Not automatically. MRI severity and symptom severity frequently do not match. Many patients with "severe" MRI findings have mild symptoms. Some with "mild" findings have significant pain. These terms require interpretation by a spine specialist in the context of your examination — the report alone cannot tell you how serious your condition is.
Do all MRI findings need treatment?
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No. Many spine MRI findings are incidental — present on imaging but not causing symptoms. Whether a finding needs treatment depends on whether it is clinically significant — causing nerve-related symptoms, progressive weakness, or functional limitation. A spine specialist consultation is the right way to assess this.
Where can I get my MRI report explained in Hyderabad?
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The spine team at Pure Ortho Hospitals, Sainikpuri, Hyderabad will explain your report in plain language and correlate findings with your examination during a consultation — giving you a clear, honest picture of what it means and what needs to be done.
An MRI report is only half the picture. Bring it to Pure Ortho Hospitals, Sainikpuri, Hyderabad and the spine team will tell you exactly what it means for you — in language you can understand.
This article is for patient education only. Please consult a qualified spine specialist before making any treatment decisions based on imaging findings alone.
