同种异体冻干辐照骨板在椎管重建过程中的应用

目的探讨同种异体冻干辐照骨板在椎板切除术后椎管重建中的作用。方法对12只成年雄性绵羊行L3～L4和L4～L5全椎板切除,于其中一处用“H”型同种冻干辐照骨板覆盖,另一处作自身空白对照。于术后4、8、12、16、20、24周取材,行大体X线平片和组织切片检查,观察椎管的重建过程。结果术后4周在实验节段可见同种骨板形态、位置保持完好,椎管内无狭窄,硬膜囊无压迫;镜下椎板咬除缘有多量新生骨小梁生成,周边有大量软骨细胞及其分泌黏多糖和坏死后所留下空腔,骨板内侧有增生纤维组织及少量炎症细胞浸润。术后24周实验节段椎管重建已基本完成,覆盖骨板吸收贻尽,并与再生椎板融合,椎管形态完好,硬膜外未见瘢痕组织。重建节段与对照节段相比硬膜粘连程度明显减轻（P〈0．01）,椎管内容积无明显改变,硬膜囊形状保持良好,无明显压迫。结论同种冻干辐照骨板具有良好的生物相容性、生物力学性能和诱导成骨作用,是一种良好的硬膜外覆盖材料,可用于节段性椎管重建术。

Application of allogeneic freeze-drying radiation bone sheet in vertebral canal reconstruction

Objective] To study the value of allogeneic freezedrying,radiation sterilization bone sheet in vertebral canal reconstruction in sheep.Methods] L_3-L_4 and L_4-L_5 laminectomy were performed in twelve adult mail sheep.After laminectomy,one site of L_3-L_4 or L_4-L_5 was covered with allogeneic freeze-drying,radiation sterilization bone sheet in "H" shape while the other site was remained as control.The sheep were killed and the specimen were retrieved in 4,8,12,16,20 and 24 weeks respectively after operation to observe scar formation process.Results] Compared with the control segment,the dura adhesion degree in the laminoplasty segment decreased significantly(P<0.01),and the dura sac remained in good shap.There was no distinct compression to the dura.Conclusion] Due to its good biocompatibility,biomechanical characters and osteogenic ability,allogeneic freeze-drying,radiation sterilization bone sheet is an ideal material for vertebral canal reconstruction.