Understanding Your Spine MRI Report: A Patient's Guide

What Is a Spine MRI?

An MRI (Magnetic Resonance Imaging) uses powerful magnets and radio waves to create detailed images of the bones, discs, nerves, and soft tissues of your spine. Unlike X-rays or CT scans, MRI does not use radiation. It is the gold standard for evaluating disc problems, nerve compression, spinal cord issues, and tumours.

Your MRI report is written by a radiologist and describes what they see on the images. It is important to remember that the report describes anatomy, not symptoms. A finding on MRI does not automatically mean you need treatment — your doctor must correlate the report with your symptoms and clinical examination.

Common MRI Terms Explained

Disc Bulge

A disc bulge means the outer ring of the intervertebral disc extends beyond the edges of the vertebral bodies. It is extremely common — studies show that over 50% of people above age 40 have disc bulges on MRI without any symptoms. A disc bulge alone is rarely a cause for concern and almost never requires surgery.

Disc Protrusion

A protrusion is a type of disc herniation where the disc material pushes outward but the base of the herniation is wider than the part that protrudes. Think of it like pressing your thumb into a balloon — the balloon bulges out but doesn't pop. Protrusions can press on nerve roots and cause pain, but many are managed conservatively with medication and physiotherapy.

Disc Extrusion

An extrusion is more significant. Here, the disc material breaks through the outer ring and the protruding portion is narrower at its base. This is more likely to cause nerve compression and symptoms like sciatica or limb weakness. Extrusions may resolve on their own over months, but larger ones sometimes require surgical removal.

Disc Sequestration

Sequestration means a fragment of disc material has broken off completely and is sitting freely in the spinal canal. This can compress nerves significantly and often (though not always) requires surgical intervention, especially if it causes progressive weakness or bladder symptoms.

Other Terms You May See

Spinal Stenosis

Stenosis means narrowing. Spinal stenosis refers to narrowing of the spinal canal or the neural foramina (the openings through which nerves exit the spine). Mild stenosis is common with ageing. Moderate to severe stenosis may compress the spinal cord or nerve roots, causing pain, numbness, or difficulty walking. Significant stenosis that causes symptoms may need spinal decompression surgery.

Modic Changes

Modic changes describe signal changes in the vertebral bone marrow adjacent to a damaged disc. They are graded into three types:

• • Modic Type 1: Inflammation and swelling — often associated with active back pain
• • Modic Type 2: Fatty replacement — more stable, may or may not cause symptoms
• • Modic Type 3: Bony sclerosis (hardening) — least common, usually chronic changes

Annular Tear (or Annular Fissure)

An annular tear is a small crack or rupture in the outer ring (annulus fibrosus) of the disc. This can be a source of back pain, particularly if it is a high-intensity zone (HIZ) on MRI. However, annular tears are common in asymptomatic individuals too, and most heal with conservative care.

Desiccation (Disc Dehydration)

Disc desiccation means the disc has lost water content. On MRI, a healthy disc appears white (bright signal on T2 images), while a desiccated disc looks dark. This is a normal part of ageing and is not a disease by itself. It is essentially the same as degenerative disc disease.

Listhesis (Spondylolisthesis)

Listhesis means one vertebra has slipped forward (or backward) relative to the one below it. It is graded from Grade 1 (mild, up to 25% slippage) to Grade 4 (severe, more than 75% slippage). Low-grade listhesis is often managed conservatively. Higher grades with instability or nerve compression may require surgical stabilisation.

What Your Doctor Looks For

When a neurosurgeon like Dr. Sayuj Krishnan reviews your MRI report, they are not just reading the radiologist's findings. They are looking for a correlation between the MRI, your symptoms, and your clinical examination. Here is what matters most:

What Is Normal vs What Is Concerning

When MRI Findings Need Surgery vs Conservative Care

The vast majority of spine MRI findings do not require surgery. Conservative treatment — including medications, physiotherapy, lifestyle changes, and time — resolves symptoms for most patients. Surgery is considered when:

• • Conservative treatment has failed after 6–12 weeks of an adequate trial
• • There is progressive neurological weakness (foot drop, hand clumsiness)
• • Bladder or bowel dysfunction develops (cauda equina syndrome — an emergency)
• • There is severe spinal cord compression with myelopathy signs
• • A tumour or infection requires surgical biopsy or removal

Dr. Sayuj Krishnan always takes a conservative-first approach. When surgery is needed, minimally invasive endoscopic techniques are preferred wherever possible, allowing faster recovery and smaller incisions.

Tips for Patients Reading Their MRI Reports