Vertebroplasty and kyphoplasty: is one of these procedures the best choice for all patients?

Vertebral compression fractures (VCFs) are a widespread problem in elderly populations, with approximately 700,000 VCFs occurring in the United States each year as a result of osteoporosis. Vertebroplasty and kyphoplasty are two minimally invasive procedures that are increasingly used to treat VCFs. Both procedures stabilize VCFs by injecting bone cement into the vertebral body, with kyphoplasty having the additional step of reducing the fracture with an inflatable bone tamp (IBT). Both of these procedures provide excellent pain relief for most patients, with a low incidence of serious complications. It has been suggested, however, that kyphoplasty may afford a lower risk of clinical complications than vertebroplasty. Use of the IBT can elevate the vertebral endplates toward their prefracture levels and create an intravertebral cavity. This cavity allows for the injection of more viscous cement under lower pressure, which may result in a lower rate of clinically significant cement leaks. In addition to creating a cavity, the potential fracture reduction would restore vertebral height and correct kyphotic deformity. This can reduce the risk of serious comorbidities related to kyphotic deformity, many of which involve pulmonary dysfunction. It has also been suggested that kyphotic deformity resulting from VCFs might increase the risk of subsequent VCFs (1). Recently, there have been reports of height restoration and kyphosis correction in a few vertebroplasty studies. These studies found the greatest degree of height restoration in vertebrae exhibiting intravertebral clefts, or pseudarthosis. In some of these studies, physicians were able to manipulate the spine through padding and positioning during the procedure. Although height restoration and kyphosis correction were observed, they were not to the same degree as that observed in published kyphoplasty studies (2). The low cost and short procedural time associated with vertebroplasty make the procedure an attractive choice for VCFs not exhibiting a high degree of kyphotic deformity or vertebral height loss. Although vertebroplasty may successfully treat the pain experienced by patients with severe vertebral deformity, it does not address deformity to the same degree as kyphoplasty. Because of the risks and comorbidities often associated with kyphotic deformity, it is a common symptom of VCFs that needs to be addressed. The degree of height restoration and kyphotic deformity correction experienced by kyphoplasty patients leads me to believe that it may become the standard of care for VCFs under certain circumstances. In a 2003 publication by Fourney and colleagues (3), both procedures were performed using a decision tree to determine which procedure was best for which patients. They performed kyphoplasty for patients with significant vertebral collapse, kyphosis greater than 20°, or disruption of the posterior vertebral cortex, whereby more controlled cement delivery was advantageous to minimize risks of spinal compromise. In the future, I believe many clinicians may use decision trees of this nature to determine which procedure is best for each individual case.