可注射硫酸钙/羟基磷灰石复合物作为经皮椎体成形术填充物的实验研究

Experimental study on injectable calcium sulphate and hydroxyapatite compounding as implant in Percutaneous Vertebroplasty

目的探讨椎体成形术的有效填充材料。方法采用PVP技术将40%可注射硫酸钙/羟基磷灰石(CSH/HA)复合物注入实验兔L6椎体内,L5椎体作为对照,于术后2、4、6、8、10、12周行影像学、组织学观察及骨组织计量学测定。结果影像学显示:术后4周实验椎体填充区密度明显高于周围松质骨密度,术后10～12周实验椎体填充区密度与周围松质骨一致。不脱钙骨组织学检查显示:术后4周复合物降解不明显,已出现成骨效应,6周实验椎体填充区内材料明显降解及出现新生骨小梁,8周实验椎体缺损边缘和中心部分的骨小梁逐渐成熟,10～12周椎体缺损已完全修复,为成熟的骨小梁组织所填充。骨组织计量学测定显示:术后10～12周实验椎体填充区骨小梁百分比及厚度与周围松质骨无显著差异。结论40%CSH/HA复合物在实验动物椎体内降解时间合适,成骨效应良好,新骨形成质量好,能有效修复椎体缺损,因而可能是一种理想的PVP填充物。

Objective To study the effective injectable implant for percutaneous vertebroplasty（PVP）. Methods 40% Injectable calcium sulphate and hydroxyapatite compounding was injected into rabbit L6 vertebral bodies through PVP tech- nique with L5 vertebral bodies as control. 2,4, 6, 8, 10, 12 weeks after injection radiological and histological and bone histomorphometric examination were performed. Results Radiological examination showed that 4 weeks after injection density of injected area is higher than adjacent cancellous bone. 10 - 12 weeks after injection density of injected area is the same as adjacent cancellous bone. Undecalcified histological examination showed that 4 weeks after injection compo- unding degraded less with obvious bone formation effects. 6 weeks after injection obvious material degradation and new trabecular bone was observed in L6 vertebral body defect area. 8 weeks after injection new trabecular bone in the center and at the edge of defect area began to mature. 10 - 12 weeks after injection the defect area was fully repaired with mature trabeculae. Bone histomorphometric examination showed that 10 - 12 weeks after injection there was no significant difference in trabecular area and thickness between defect and adjacent cancellous bone. Conclusion 40% injectable calcium sulphate and hydroxyapatite compounding in rabbit vertebral bodies has suitable degradation time and good bone formation effect, and can repair vertebral body defect effectively with new formed good quality trabeculae. Thus it may be an ideal implant in Percutaneous Vertebroplasty.