Percutaneous vertebroplasty: an experimental study with three different filling materials
LIU Hong jian 1* , DU Jing yuan 1, HAN Song hui 2, LIU Hui 3, LIANG Hui min 1(1. Department of Orthopaedics, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 430022, China; 2. Division of Interventional Radiology, Luoyang Institute of Traditional Chinese Orthopedics and Traumatology, Luoyang 471002, China; 3.the First Affiliated Hospital, Henan University of Science and Technology, Luoyang 471003, China)
Objective To investigate the key operation of percutaneous vertebroplasty (PVP) in osteoporotic goats treated with polymethylmethacrylate (PMMA), calcium phosphate cement (CPC) and rhBMP 2/CPC, and observe the radiological appearance of PVP. Methods Bone mineral density (BMD) was measured with Dual Energy X ray Absorptionmetry (DEXA). Six to seven years old healthy goats ( n =14) were divided to three groups randomly: normal group ( n =2); sham operation group ( n =2) and operation group underwent ovariectomy (OVX) ( n =10). Four months later, the BMDs of all goats were measured again. Total 6 goats, 2 goats from each group, were sacrificed and removed the vertebral cancellous bone. Histology examination proved the OVX group coincidence as the osteoporosis big animal model. For every ewe vertebra (L2-L6), we select two vertebra at random, which were augmented with PMMA, CPC and rhBMP 2/CPC under intravenous anaesthesia, axial C arm control. The filling material is different in two vertebra of each ewe respectively. Results PVP was performed successfully in 8 ewe 16 vertebra. No significant difference in the three different materials was found in injected volume ( P 0.05).The injected resistance of PMMA was hard and the working time was 2-3 minutes; by contraries, the CPC and rhBMP 2/CPC were easy to injecte and the working time was 3-5 minutes. Postoperative CT showed the filling material was pockety, 5 vertebral showed leakage, the rates of cement leakage was 31.3%. Conclusion The aged ewe of OVX was a good model to study PVP. CPC and rhBMP 2/CPC were better than PMMA in injected resistance and working time.