Does an X-ray (X-ray) show nerve root compression?

X-rays Do NOT Show Nerve Root Compression

X-rays cannot visualize nerve roots or soft tissue structures that cause nerve root compression—MRI is required for this diagnosis. 1

Why X-rays Are Inadequate

X-rays only show bony structures and cannot depict:

• Nerve roots themselves (soft tissue structures invisible on plain radiographs) 1
• Disc herniations (the most common cause of nerve root compression) 1
• Soft tissue pathology including ligamentum flavum hypertrophy, epidural masses, or spinal cord abnormalities 1
• Neural foraminal soft tissue narrowing from disc bulges or herniations 1

While X-rays may show indirect bony changes like facet joint hypertrophy, uncovertebral joint hypertrophy, or decreased disc space height that suggest potential nerve root compression, they cannot confirm actual nerve root involvement. 1

The Gold Standard: MRI Without Contrast

MRI without IV contrast is the imaging study of choice for diagnosing nerve root compression, with 88% accuracy in predicting surgically confirmed nerve root lesions—far superior to CT (50%), conventional myelography (57%), and even CT myelography (81%). 2, 3

When to Order MRI:

• Radiculopathy symptoms that have failed 6 weeks of conservative management in patients who are surgical or interventional candidates 1, 2
• Physical examination signs of nerve root irritation with persistent or progressive symptoms 1
• Red flag symptoms including progressive neurologic deficits, suspected cauda equina syndrome, or concern for malignancy/infection 1

MRI Diagnostic Capabilities:

• Directly visualizes nerve root compression from disc herniations, spinal stenosis, or other soft tissue pathology 1, 2
• Shows the relationship between disc material and nerve roots, grading contact, deviation, or frank compression 4
• Assesses spinal canal patency and vertebral marrow for alternative diagnoses 1

Critical Pitfall: MRI Findings Must Correlate Clinically

Do not rely on imaging alone—degenerative findings are extremely common in asymptomatic patients. Approximately 65% of asymptomatic patients aged 50-59 years show significant cervical spine degeneration on imaging, and 20-28% of asymptomatic individuals have lumbar disc herniations. 1, 2

The key is clinical-radiological correlation: MRI abnormalities must match the patient's dermatomal pain pattern, physical examination findings (positive straight leg raise, specific dermatomal sensory loss, reflex changes), and symptom distribution. 1, 5

Alternative Imaging When MRI Is Unavailable

CT myelography is the second-line option when:

• MRI is contraindicated (pacemakers, certain implants, severe claustrophobia) 1, 3
• MRI findings are equivocal or nondiagnostic 1
• Significant metallic hardware artifact limits MRI interpretation 3

CT myelography provides excellent visualization of nerve roots and can diagnose foraminal stenosis and nerve root compression, though it requires an invasive lumbar puncture procedure. 1

Bottom Line Algorithm

1. X-rays cannot and will not show nerve root compression 1
2. Order MRI lumbar or cervical spine without contrast for suspected nerve root compression after 6 weeks of failed conservative therapy or with red flag symptoms 1, 2
3. Correlate MRI findings with clinical examination—imaging abnormalities must match the patient's specific radicular pattern 1, 2
4. Reserve CT myelography for MRI contraindications or equivocal MRI results 1, 3