Experimental Studies of Kyphoplasty with the Domestic Polymethylmetharylate and Injectable Calcium Phosphate Cement

Objective To investigate the biomechanical changes of isolated, fractured VBs after treatment by Kyphoplasty(KP) with one of two domestic cements: polymethylmetharylate(PMMA) or injectable calcium phosphate cement(CPC). Methods Sixty VBs were harvested from embalmed cadavers. According to their BMD,The VBs were divided into: normal (A);osteoporotic (B);and serious osteoporotic group(C). All VBs were compressed in a materials testing machine to determine initial intensity and stiffness values, were assigned to one of two groups, and were then repaired using KP with the domestic PMMA or CPC. Re-compressed as pretreatment to determine post-treatment intensity and stiffness values. The volumes of the expanded IBT(an inflatable tamp) and injected cement were recorded.Results The pretreatment intensity and stiffness were recovered in all VBs of groups B and C, whereas not recovered in group A. The heights of VB were recovered to 95% of initial ones. Extravasation was not found in either VBs.Conclusion CPC can be used in KP, but have yet to be substantiated in more studies.