颈椎椎间融合器融合效果的在体动物研究

In vivo experimental study of cervical intervertebral fusion cage

目的在活体山羊颈椎上比较三面皮质自体骨、垂直圆柱体Harmscage及方盒形Carboncage的椎间融合效果。方法取24只成年雄性山羊,随机分为三组:自体骨组、Harmscage组及Car-boncage组。所有动物均行C3-4椎间盘切除术并分别植入以上内植物。于术前、术后即刻及术后1、2、4、8、12周摄颈椎正侧位X线片,于侧位X线片上测量平均椎间高度、椎间角及前凸角;术后12周处死动物,取C3,4节段标本进行组织学评估。结果术后1周Carboncage组的平均椎间高度、椎间角及前凸角大于Harmscage组和自体骨组(P<0.05);术后12周两个cage组的平均椎间高度、椎间角及前凸角均大于自体骨组,差异有统计学意义(P<0.05)。术后12周依据融合分级标准对三组进行影像学评估,和自体骨组比较,两个cage组的骨融合效果略好,但无统计学意义;组织形态学亦发现两个cage组的椎间融合效果较好,但与自体骨组比较差异无统计学意义。垂直圆柱体Harmscage中形成的新生骨量多于方盒形Carboncage。结论方盒形Carboncage具有良好的椎间支撑能力,而垂直圆柱体Harmscage的椎间融合效果更好。

Objective To evaluate the characteristics of intervertebral fusion using autologous tricortical iliac crest graft, Harms cage and Carbon cage in the goat cervical spine models. Methods Twenty-four goats underwent C3-4 discectomy and intervertebral fusion, the later was achieved each with 8 goats by the following methods: Group 1, autologous tricortical iliac crest bone graft; Group 2, Harms cage filled with autologous iliac crest graft; Group 3, Carbon cage filled with autologous iliac bone graft. Radiography was performed pre- and post- operatively and after 1, 2, 4, 8, and 12 weeks. At the same time points, disc space height (DSH), intervertebral angle (IVA), and lordosis angle (LA) were measured. After 12 weeks, the goats were killed and fused segments were harvested. All cervical fusion specimens underwent histomorphological studies. Results One week after operation, the DSH, IVA and LA of Carbon cage fused group were statistically greater than those of autologous iliac bone graft and Harms cage fused group (P<0.05). The values for DSH, IVA and LA were significantly higher in cage-treated goats than that in bone graft over a 12-week period (P<0.05). Both of radiographic and histomorphologic evaluation revealed better fusion in two cage groups than in autologous bone group, but there was no any statistical significance. Conclusion Box shaped Carbon cage can provide a good intervertebral support, and vertical cylindrical Harms cage can get better intervertebral fusion.