What is the best initial imaging study for a 55-year-old female on hemodialysis (renal replacement therapy) with a history of fall and complaining of pain in the thoracolumbar spine?

Initial Imaging for Thoracolumbar Spine Trauma in a 55-Year-Old Female on Hemodialysis

CT of the thoracolumbar spine without IV contrast is the best initial imaging study for this patient, as it is the gold standard for detecting thoracolumbar fractures with 94-100% sensitivity, far superior to plain radiographs. 1

Why CT is Superior to Plain Radiographs

• Plain radiographs have poor sensitivity for thoracolumbar fractures, detecting only 49-62% of thoracic spine fractures and 67-82% of lumbar spine fractures 1
• CT demonstrates 94-100% sensitivity for identifying thoracolumbar spine fractures, making it the diagnostic gold standard 1
• This patient meets high-risk criteria for imaging: she is >60 years of age (55 years old), has midline thoracolumbar pain after a fall, and is on hemodialysis (which increases osteoporosis risk) 1

Practical Imaging Approach

Initial Study

• Order CT thoracolumbar spine without IV contrast as the primary diagnostic test 1
• If the patient is already getting CT chest/abdomen/pelvis for other trauma evaluation, sagittal and coronal spine reformats from existing data are equally effective (94-99% sensitivity) and radiation-sparing 1
• The most commonly missed fractures on routine body CT protocols are nondisplaced transverse process and minor endplate fractures that don't alter management 1

When to Add MRI

• Add MRI thoracolumbar spine if any neurological deficits are present (weakness, numbness, bowel/bladder dysfunction) to evaluate for spinal cord injury, disc herniation, or epidural hematoma 1
• MRI changes management in 16-24% of cases by better visualizing posterior ligamentous complex injuries and detecting additional fractures missed on CT 1
• MRI is essential if there is concern for ligamentous instability or if surgical planning is needed 1

Critical Considerations for This Patient

Hemodialysis-Specific Concerns

• Avoid IV contrast unless absolutely necessary due to her renal failure status 1
• Increased fracture risk: Hemodialysis patients have higher rates of osteoporosis and pathologic fractures, making thorough evaluation crucial 1

Common Pitfalls to Avoid

• Do not rely on plain radiographs alone in this high-risk patient—they will miss 18-51% of fractures 1
• Screen the entire spine: 20% of spine injuries have a second noncontiguous spinal fracture 1
• Do not delay imaging if any neurological symptoms develop—this requires immediate MRI evaluation 1

If Plain Radiographs Are Obtained First

• If radiographs are performed (not recommended as initial study), they should include anteroposterior and lateral views of both thoracic and lumbar spine, plus a swimmer's lateral view of upper thoracic spine if obscured by shoulders 1
• Any abnormal or equivocal findings on radiographs mandate CT follow-up 1

Algorithm Summary

1. First-line: CT thoracolumbar spine without IV contrast 1
2. If neurological deficits present: Add MRI thoracolumbar spine without IV contrast 1
3. If concern for infection/malignancy: MRI without and with IV contrast (though contrast should be used cautiously given renal failure) 1