医用硫酸钙在家兔腰椎融合模型中的成骨能力

[目的]通过与自体髂骨进行比较,评价医用硫酸钙单独应用的成骨能力,并探讨其可能的成骨机理。[方法]建立家兔腰椎后外侧融合模型,以自身作为对照,双侧横突间植骨,左侧植入硫酸钙颗粒,右侧植入自体髂骨。于术后3、6、12周行X线、CT及组织学检查。[结果]术后3周,硫酸钙尚可见残留颗粒,自体骨完全降解;植骨区域内均可见到大量的破骨细胞,并有血管纤维组织长入。术后6周,硫酸钙完全降解,影像学检查两者之间没有明显的差异,表现为局部骨密度增高,新骨成形;组织学检查两侧植骨区内均为大量的透明软骨形成,自体髂骨植骨区内可见散在的骨小梁结构。术后12周,组织学及影像学上二者没有任何的差别,两侧形成的骨组织与家兔的椎体骨组织结构相同。[结论]医用硫酸钙作为骨移植替代材料,除了具有良好的骨传导性外,硫酸钙可能还具有骨诱导性,其成骨能力与自体髂骨相当,医用硫酸钙单独应用可以取得良好的融合效果。

Osteogenetic ability of calcium sulfate applied in rabbit lumbar spinal fusion model

[Objective]To investigate the osteogenetic ability of calcium sulfate applied alone by comparing with that of autograft harvested from ilium crest and discuss the possible osteogenetic mechanism.[Method]A rabbit lumbar posterolateral spinal fusion model was established.The left zygapophyseal joint was implanted with calcium sulfate tablet,and the right with iliac crest bone graft.Radiographic analysis and decalcified histological evaluation were performed.[Result]At 3 weeks,residual calcium sulfate tablet could not be noted by X-ray and CT scan,while autograft can't be seen,histological assessment revealed the degeneration velocity of calcium sulfate was slower than that of autograft.Ingrowth of blood vessel tissue and osteo-blast could be seen in both sides.At 6 weeks,there were no difference between both sides,histological assessment revealed cartilage formation in both sides.At 12 weeks,there was no difference by radiographic and histological assessment between both sides,proliferative bone formation was similar with lumbar body.[Conclusion]Calcium sulfate plays the similar role to iliac crest bone graft when used alone in promoting spinal fusion in rabbit model.Calcium sulfate has good osteo-conductivity,perhaps has osteo-inductivity,so is a good bone graft substitute.