Book Description
Up to 1/3 of all cancer patients develop metastases to the spinal column and over 50% of spinal metastases with neurologic manifestations in females are found to arise from primary breast neoplasms (3). Burst fracture can arise in such bones compromised by tumor and is deemed one of the most difficult injuries of the spine to treat successfully, in part because the exact injury mechanism is not well understood. Using a combination of finite element modeling, materials and mechanical testing we aim to quantify fracture risk in metastatically involved vertebral bodies in order to both understand the mechanism of such fractures and develop a definitive set of clinical guidelines for the prophylactic treatment vertebral body metastases. To this end, we have developed an experimental protocol to analyze biphasic material properties of tumor specimens. We have constructed a poroelastic two-dimensional axis-symmetric finite element model of the vertebral body and adjacent intervertebral disc which has enabled us to parametrically assess the effects of rate dependence on vertebral body strength and validate the importance of utilizing poroelastic theory in the consideration of metastatic involvement. This progress provides us the needed basis for our three- dimensional modeling and experimental validation necessary to quantify burst fracture risk.
