Osteoporotic vertebral fractures and collapse with intravertebral vacuum sign (Kümmel's disease).

The intravertebral vacuum phenomenon was first described by Kümmel and is also known as delayed vertebral collapse or vertebral pseudarthrosis. Clinically, it occurs in approximately 10% of vertebral osteoporotic fractures, mainly in the thoracolumbar zone, is accentuated on extension views and associated with benign fractures. Most patients are neurologically intact, and continued pain is a common symptom that responds well to stabilization. Various theories exist in the literature about the pathogenesis; data support a combination of ischemia and psuedarthrosis. The ultimate treatment plan must be individualized and involve decompression of neurologic elements--when present--and sufficient stabilization, which varies according to surgeon preference and the patient's combordities.