What diagnostics are indicated for a male patient presenting with left-sided weakness from the upper back to the foot with a history of spine complaints?

Diagnostic Approach for Left-Sided Weakness with History of Spine Complaints

MRI of the spine without and with contrast is the most appropriate initial diagnostic test for a patient presenting with left-sided weakness from upper back to foot with history of spine complaints, as it can rapidly identify potential spinal cord compression requiring urgent intervention. 1

Initial Diagnostic Workup

Laboratory Tests

• Complete blood count (CBC)
• Erythrocyte sedimentation rate (ESR)
• C-reactive protein (CRP)
• Blood cultures if infection is suspected

Imaging Studies

First-Line Imaging:

• MRI of the spine without and with IV contrast 1
  • Covers the entire affected region (cervical, thoracic, and lumbar spine)
  • Provides excellent visualization of:
    • Spinal cord compression
    • Epidural abscess
    • Disc herniation
    • Vertebral body abnormalities
    • Paraspinal soft tissue involvement
  • Contrast enhancement helps identify infectious processes and differentiate between abscess and other pathologies

When MRI is contraindicated or unavailable:

• CT of the spine 1
  • Less sensitive than MRI for soft tissue and spinal cord abnormalities
  • Better for detecting bony abnormalities
  • May be followed by CT myelography if needed

Clinical Decision Algorithm

1. Immediate MRI without and with contrast if any of these are present:

   • Progressive neurological deficits
   • Severe weakness
   • Signs of cauda equina syndrome (urinary retention, saddle anesthesia)
   • Suspected infection (fever, elevated inflammatory markers)
   • History of cancer 1, 2

2. Plain radiographs are NOT recommended as the initial test for this presentation as they are insensitive for detecting spinal cord compression 1

3. Consider abbreviated MRI protocol in emergent settings:

   • Sagittal STIR + axial T2 sequences can detect spinal cord compression with 100% sensitivity 3
   • This can expedite diagnosis while maintaining diagnostic accuracy

Specific Considerations Based on Clinical Suspicion

If Infection is Suspected:

• MRI without and with contrast is the gold standard 1
• Look for:
  • Vertebral endplate erosions
  • Disc space narrowing
  • Epidural abscess
  • Paraspinal soft tissue enhancement

If Trauma is Suspected:

• CT spine is appropriate for initial assessment of fractures 1
• Follow with MRI to evaluate spinal cord and soft tissue injuries 1

If Degenerative Disease is Suspected:

• MRI without contrast may be sufficient 2
• Evaluate for:
  • Disc herniation with nerve root compression
  • Spinal stenosis
  • Foraminal narrowing

Important Caveats

• Avoid routine imaging in patients with nonspecific back pain without neurological deficits 1, 4
• Be aware that imaging findings may not correlate with symptoms - up to 67% of asymptomatic individuals have disc protrusions on MRI 5
• Recognize that left-sided weakness from upper back to foot suggests a potentially serious condition that requires prompt evaluation, as this distribution of weakness indicates possible spinal cord or multiple nerve root involvement 6
• Consider the entire clinical picture - the pattern of weakness (unilateral, involving multiple levels) strongly suggests a structural lesion requiring immediate imaging rather than a functional disorder 1, 6

Follow-up Testing

• If initial MRI is negative but symptoms persist:
  • Consider electromyography and nerve conduction studies
  • Consider vascular imaging if spinal cord infarction is suspected
  • Re-evaluate with repeat MRI if symptoms progress

The patient's presentation of left-sided weakness from upper back to foot with a history of spine complaints warrants urgent evaluation with MRI to rule out potentially serious and treatable causes of spinal cord compression.