What is the initial workup for a patient presenting with a vertebral compression fracture?

Workup for Vertebral Compression Fracture

Initial Imaging: Start with Plain Radiographs

Begin with anteroposterior and lateral radiographs of the spine, which are the appropriate first-line imaging study for suspected vertebral compression fractures, particularly in patients with osteoporosis or chronic steroid use. 1

• Upright radiographs provide functional information about axial loading and can identify new compression fractures when compared to prior films 1
• Flexion and extension views can evaluate spine stability 1
• Critical limitation: Radiographs have poor sensitivity for detecting early fractures and cannot assess fracture acuity or distinguish benign from pathologic causes 1

Essential MRI Without Contrast

If radiographs confirm a compression fracture OR if radiographs are negative but clinical suspicion remains high, proceed immediately to MRI of the affected spine region without IV contrast. 1, 2

Key MRI sequences and what they reveal:

• STIR or fat-saturated T2-weighted sequences are the single most important sequences, showing bone marrow edema that indicates an acute/unhealed fracture 1
• T1-weighted sequences identify fracture clefts (linear bands of hypointensity) and assess overall vertebral body integrity 1
• MRI distinguishes benign osteoporotic fractures from pathologic fractures by identifying convex posterior vertebral body border, extension into posterior elements, and abnormal marrow signal patterns 1
• MRI demonstrates spinal canal compromise from retropulsed fracture fragments and assesses for spinal cord or nerve root compression 1

Important caveat: Bone marrow edema typically resolves within 1-3 months, so edema presence does not precisely date the fracture but indicates it is relatively acute 1

When to Add IV Contrast to MRI

Upgrade to MRI without and with IV contrast only when there is clinical suspicion of underlying malignancy, infection, or inflammation. 1

Specific "red flag" indications for contrast-enhanced MRI:

• Known history of cancer (the only red flag with proven increased probability of spinal malignancy) 1
• Unexplained fever, elevated inflammatory markers, or bacteremia suggesting vertebral osteomyelitis 1
• Immunosuppression 1
• Atypical pain patterns or fracture from minimal trauma 1, 2

Contrast with fat suppression is invaluable for identifying epidural tumor extension, paraspinal involvement, and distinguishing infection from malignancy 1

Supplementary CT Imaging

Reserve CT spine without IV contrast for specific scenarios where MRI findings need clarification or MRI is contraindicated. 1

• CT provides superior detail of fracture extension to the posterior column, pedicle integrity, and posterior cortex assessment 1
• CT is equal to MRI for predicting significant spinal stenosis and excluding cauda equina impingement 1
• Use CT when: Evaluating osseous integrity in pathologic fractures, assessing vertebral body comminution, or when patient cannot undergo MRI 1

Laboratory Workup

While not explicitly detailed in the imaging-focused guidelines, obtain:

• Complete blood count, erythrocyte sedimentation rate, and C-reactive protein if infection is suspected 1
• Serum protein electrophoresis and urine protein electrophoresis if multiple myeloma is a consideration 3, 4
• Bone metabolism markers (calcium, phosphate, alkaline phosphatase, vitamin D, parathyroid hormone) to assess underlying metabolic bone disease 4

Advanced Imaging for Specific Scenarios

When standard imaging is indeterminate:

FDG-PET/CT whole body is appropriate as a follow-up study (not initial imaging) to distinguish benign from pathologic compression fractures when MRI and CT are indeterminate. 1

For patients with known malignancy:

• MRI of the complete spine without and with IV contrast is the appropriate comprehensive study to evaluate for multiple metastatic lesions 1
• Use the Spinal Instability Neoplastic Score (SINS) to classify stability: stable (0-6), potentially unstable (7-12), or unstable (13-18) 1, 2

When biopsy is needed:

Image-guided biopsy of the spine is appropriate when imaging findings are ambiguous and cannot definitively distinguish benign from pathologic fracture. 1

Critical Physical Examination Components

Document the following at initial presentation to establish baseline and identify indications for urgent intervention:

• Point tenderness at the spinous process of the fractured vertebra is the classic finding 1
• Complete lower extremity neurological examination including motor strength, sensation, reflexes, and rectal tone 1, 2
• Assess for radicular pain patterns suggesting nerve root compression 1
• In patients with multiple compression fractures, physical examination under fluoroscopic guidance can localize the acute painful level 1

Common Pitfalls to Avoid

• Do not rely solely on radiographs when clinical suspicion is high—up to two-thirds of vertebral compression fractures are missed on plain films alone 4
• Do not skip MRI in patients with known malignancy presenting with new back pain, as distinguishing benign from pathologic fractures is critical for management 1, 2
• Do not order MRI with contrast alone without the non-contrast sequences, as interpretation requires correlation with standard non-contrast sequences 1
• Do not delay neurological examination—missing baseline deficits can lead to inappropriate conservative management of unstable fractures 2, 5