Pathogenesis of the intravertebral vacuum of Kümmell's disease.

In this review, we explored the progress of the pathogenesis of Kümmell's disease intravertebral vacuum. Using different expressions of the same disease including 'Kümmell's disease', 'avascular necrosis after vertebral compression fracture (VCF)', 'post-traumatic vertebral osteonecrosis', 'vertebral pseudarthrosis', 'intravertebral vacuum (cleft or gas)', 'delayed vertebral collapse', 'VCF nonunion', and by conducting a search of the PubMed database, we analyzed the results to examine the pathogenesis of the intravertebral vacuum of Kümmell's disease after referring to pertinent literature on intravertebral vacuum of ischemic necrosis after VCF, and exploring the progress of pathogenesis of this disease. A number of discrepancies were identified within the pathogenesis of the intravertebral vacuum after VCF. There were statements such as avascular necrosis of the vertebral body, bone biomechanics, gas forming and other types of claims, all of which obtained clinical and biomechanical supporting evidence. Collectively, most of the researchers believe that Kümmell vertebral fracture syndrome was the comprehensive effect of multiple factors including osteoporosis, avascular necrosis of the vertebral body, and biomechanical changes following fracture. However, there are a number of discrepancies to be resolved and future studies are therefore needed.