Augmentation of Calcium Phosphate Cements with Bone Morphogenetic Proteins for Vertebroplasty

Osteoporosis is a condition that decreases bone mineral density. It results in hundreds of thousands of vertebral fractures every year that debilitates people. These fractures can cause severe back pain, kyphosis, stenosis, and even mental anguish. Several non-surgical therapies as preventative measures are available to treat osteoporosis, however, these are not always successful. Surgery may be required to repair damaged tissue, such as a collapsed vertebral body One of these surgical management techniques is vertebroplasty This procedure entails injecting a bone cement into a vertebral body to reestablish the height and, more importantly, strength of the vertebrae. Currently, the state of the art in bone cement is polymethyl methacrylate (PMMA). Although reports on PMMA have suggested it has been a successful material in vertebroplasty to relieve back pain, many complications are attributed to PMMA that make it less than ideal. One of these is PMMA\u27s exothermic polymerization reaction that may cause damage to surrounding neural elements like the spinal cord. For this reason, other materials are being investigated. One of these is calcium phosphate cement. This material could prove more successful due to its similar composition to elements in bone and its nonexothermic reaction. Documented studies have already shown CPC is biocompatible and osteoconductive in femoral and craniofacial defects of animal models. Additionally, it is bioresorbable, unlike PMMA, and should remodel into bone over time. Calcium phosphate cement may also be a potential carrier for an osteoinductive factor, recombinant bone morphogenetic protein-2 (rhBMP- 2). Histomorphometric and histological assessments are required to determine whether rhBMP-2 loaded calcium phosphate cement is a successful material for vertebroplast