Which of the following is the MOST accurate imaging feature on CT that differentiates a pathological fracture through a metastasis from an insufficiency (osteoporotic) vertebral fracture?
- A Convex posterior wall with associated soft tissue mass ✓
- B Posterior cortical bulging into the spinal canal
- C Intravertebral vacuum cleft sign (Kümmell's disease)
- D Wedge-shaped anterior collapse
Correct answer: A. Convex posterior wall with associated soft tissue mass
Explanation
Convex bulging of the posterior vertebral wall combined with an associated paravertebral or epidural soft tissue mass is highly specific for pathological fracture from metastatic disease, as this reflects tumor mass beyond the fracture plane. The intravertebral vacuum cleft (Kümmell's disease) is characteristic of osteoporotic avascular necrosis of the vertebral body. Posterior cortical bulging can occur in osteoporotic fractures but without accompanying soft tissue mass. Simple anterior wedge collapse is typical of osteoporotic fracture.
Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.