What is the cause of pain radiating from the C5 and T1 nerve roots to the chest and arms?

Pain Radiating from C5 and T1 to Chest and Arms: Causes

Pain radiating from the C5-T1 nerve roots to the chest and arms is most commonly caused by cervical radiculopathy due to nerve root compression from disc herniation, foraminal stenosis, or degenerative spondylosis, though cardiac ischemia must be urgently excluded when chest pain is present.

Primary Diagnostic Considerations

Cervical Radiculopathy (Most Common Neurologic Cause)

Cervical radiculopathy occurs when nerve roots are compressed, typically by disc herniation, facet joint hypertrophy, or uncovertebral joint degeneration 1, 2. The C5-T1 distribution is particularly relevant:

• C5 radiculopathy: Pain radiates to the suprascapular region and shoulder 3
• C6 radiculopathy: Pain extends from suprascapular to posterior deltoid region 3
• C7 radiculopathy: Pain localizes to the interscapular region 3
• C8 radiculopathy: Pain affects interscapular and scapular regions 3
• T1 radiculopathy: Produces medial arm pain, chest pain (cervical angina), and hand weakness 4, 5, 6

Critical Distinction: T1 Radiculopathy and "Cervical Angina"

T1 radiculopathy is rare but uniquely presents with anterior chest pain mimicking cardiac angina 4. This occurs because T1 nerve root compression can produce:

• Anterior chest and back pain
• Medial arm numbness (T1 dermatome)
• Hand weakness, particularly affecting the abductor pollicis brevis and flexor digitorum profundus (first digit) 4, 6
• Possible Horner's sign 4

This "cervical angina" phenomenon is most commonly reported with C6, C7, and T1 radiculopathy 4.

Mandatory Cardiac Exclusion

When chest pain is present, cardiac ischemia must be ruled out first 7, 8. The 2021 AHA/ACC/CHEST Guidelines emphasize:

• Chest pain should be classified as "cardiac," "possibly cardiac," or "noncardiac" rather than using the term "atypical" 7
• Cardiac chest pain is typically substernal, provoked by exertion/stress, and relieved by rest or nitroglycerin 7, 9
• Pain that is sharp, fleeting, positional, or pleuritic suggests lower likelihood of ischemia 7
• Referred cardiac pain can involve shoulders, arms, jaw, neck, and upper abdomen 7, 9

Diagnostic Algorithm

Step 1: Immediate Triage

• 12-lead ECG immediately if any chest pain present 8
• Assess for STEMI or high-risk features requiring emergent intervention 8
• Check cardiac troponins (0/2 hour protocol with high-sensitivity troponin) 8

Step 2: Characterize the Pain Pattern

Look for these specific features:

Favoring Radiculopathy:

• Dermatomal distribution of pain/numbness 10, 11
• Neck pain with arm radiation 2, 10
• Worsening with neck movement or positioning 2
• Motor weakness in specific myotomal patterns 10
• Deep pain with or without superficial component 3

Favoring Cardiac Origin:

• Substernal pressure/squeezing 7, 9
• Exertional provocation, relief with rest 7
• Associated dyspnea, diaphoresis, nausea 9
• Diffuse, difficult to localize 7

Step 3: Physical Examination Specifics

For C5-T1 radiculopathy, examine:

• Motor testing: Specific muscle weakness patterns
  • C5: Deltoid, biceps
  • C6: Wrist extensors, biceps
  • C7: Triceps, wrist flexors
  • C8: Finger flexors, hand intrinsics
  • T1: Abductor pollicis brevis (key distinguishing feature from C8) 4, 6
• Sensory testing: Dermatomal distribution
• Reflexes: Biceps (C5-C6), triceps (C7), finger flexors (C8)
• Spurling's test: Neck extension with rotation and axial compression 10

Step 4: Imaging Strategy

If cardiac etiology ruled out and radiculopathy suspected:

Without "red flags" (no trauma, malignancy, infection, myelopathy):

• Conservative management initially for 4-6 weeks 2
• MRI cervical spine is NOT first-line unless symptoms persist or worsen 2
• Plain radiographs have limited value and rarely change management 2

With persistent symptoms or red flags:

• MRI cervical spine without and with contrast is the gold standard 1, 2
• MRI best visualizes disc herniation, foraminal stenosis, and nerve root compression 2, 10
• CT myelography if MRI contraindicated or equivocal findings 2

Common Pitfalls to Avoid

1. Assuming all chest pain with arm radiation is cardiac: T1 radiculopathy can perfectly mimic angina 4

2. Confusing C8 and T1 radiculopathy: Test the abductor pollicis brevis specifically—weakness here indicates T1, not C8 4, 6

3. Ordering MRI too early: Most cervical radiculopathy improves with conservative treatment; MRI findings in asymptomatic patients are common and can lead to overtreatment 2

4. Missing red flags: Fever, weight loss, immunosuppression, history of malignancy, progressive neurologic deficits, or myelopathic signs require urgent imaging 1, 2

5. Ignoring the 50% recurrence rate: Nearly half of patients with cervical radiculopathy have recurrent or persistent symptoms 1, 2

Additional Differential Considerations

Beyond radiculopathy and cardiac causes, consider:

• Brachial plexopathy: Pain in multiple nerve distributions, may require MR neurography 12
• Thoracic outlet syndrome: Positional symptoms, vascular compression 13
• Pulmonary embolism or aortic dissection: Life-threatening, require emergent CT imaging 8
• Musculoskeletal: Costochondritis, muscle strain (point tenderness present) 7, 14