Spine MRI: Discs, Nerves, Facet Joints and the Spinal Canal

Spine MRI provides detailed images of the discs, spinal cord, nerves, bone marrow and soft tissues, but imaging findings must be matched to your symptoms.

What does spine MRI show?

Spine MRI can assess alignment, discs, the spinal canal, spinal cord, nerve roots, facet joints, ligaments, bone marrow and surrounding soft tissues. It is commonly used for persistent neck or back pain, sciatica, radiculopathy, weakness, sensory change, trauma, infection, tumour and post-operative assessment.

What common terms mean

Disc bulge: the disc extends beyond its usual margin.
Disc protrusion or extrusion: a more focal herniation of disc material.
Stenosis: narrowing of the spinal canal or the openings where nerves exit.
Nerve root compression: contact or pressure on a spinal nerve.
Facet arthropathy: degenerative change in the small joints at the back of the spine.
Marrow oedema: increased fluid signal within bone that can have several causes.

Conventional MRI Spine vs MR Discogram

A conventional spinal MRI is primarily an anatomical examination. It shows the structure of the discs, vertebrae, facet joints, spinal canal and nerves. It can identify disc degeneration, bulging, protrusion, annular fissures and nerve compression – but these findings do not always explain a patient’s pain.

Disc degeneration is common, including in people without symptoms. A visibly abnormal disc may be incidental, while the disc responsible for pain may appear comparatively unremarkable on routine sequences. This is one reason why treatment based only on a standard MRI report can sometimes be unsuccessful.

MR discography adds a functional assessment of the intervertebral discs. It is designed to provide additional information about disc integrity and help determine which structural abnormalities may be clinically meaningful. In practical terms, it helps answer two different questions:

Anatomical MRI: What abnormalities are present?
MR discography: Which disc abnormalities may be functionally significant?

This distinction is particularly important when considering a targeted intervention such as intradiscal PRP. It is not enough to identify that a disc is degenerated; the treating team must determine whether that disc is a plausible pain generator and whether its structure remains suitable for treatment.

MR discography may help:

Distinguish potentially symptomatic disc pathology from incidental degeneration.
Assess the functional significance of an annular fissure.
Improve selection of the appropriate treatment level.
Reduce the risk of treating an abnormal-looking but clinically irrelevant disc.
Guide the precise target and method of an image-guided procedure.
Provide a more complete baseline for treatment planning and follow-up.

MR discography does not replace clinical assessment, and no imaging technique can identify the source of spinal pain in isolation. Its value lies in combining functional information with detailed anatomical imaging, the patient’s pain pattern, examination findings and medical history.

For advanced spinal treatment, diagnosis is not simply about finding an abnormality. It is about determining whether that abnormality is relevant – and whether it represents an appropriate and safely accessible treatment target.

Before and during the scan

Most spine MRI does not require fasting or contrast, but instructions vary. Contrast may be used for suspected infection, tumour, MR discography, inflammatory disease or post-operative assessment.

You will lie on your back and need to remain still. Pain can make this difficult, so take usual prescribed pain medication unless told otherwise and tell the radiographer if positioning is uncomfortable.

When symptoms need urgent assessment

Seek urgent medical care for new severe weakness, loss of bladder or bowel control, numbness around the saddle region, rapidly worsening neurological symptoms, fever with severe spinal pain, or major trauma. Do not wait for a routine outpatient MRI appointment.

Limitations and other tests

CT is often better for fine cortical bone detail and some fractures. X-ray can assess alignment, instability and weight-bearing change. No single test explains every cause of spinal pain.

Related Patient Guides

We have more detailed information on many interesting regenerative and radiological topics on our Insights page

Frequently Asked Questions

For other FAQs please visit our FAQs page

Does every disc bulge need treatment?

No. Management depends on symptoms, neurological findings and the degree of compression, not the wording alone.

Will MRI show muscle and ligaments?

Yes, although the amount of detail depends on the protocol and field of view.

Can MRI show facet-joint pain?

MRI can show facet degeneration and inflammation, but it may not prove that the joint is the source of pain.

Important: Severe or rapidly progressive neurological symptoms require urgent clinical assessment.

PATIENT GUIDE • PG-1014 [Patient information: Spine MRI provides detailed images of the discs, spinal cord, nerves, bone marrow and soft tissues, but imaging findings must be matched to your symptoms.]