组织工程骨修复山羊负重骨大段骨缺损的长期观察

目的 探讨组织工程骨修复山羊大段负重骨骨缺损的长期效果及所用支架材料珊瑚羟基磷灰石的体内最终转归情况。方法 中国青山羊15只，制备单侧胫骨2cm的骨膜与骨缺损，缺损内植入组织工程骨（珊瑚羟基磷灰石＋经诱导分化的骨髓基质干细胞）。术后早期行ECT、X线、组织学等手段检测，评价骨缺损修复情况。远期在术后6、12、18、24月行X线及组织学检查，评价骨缺损修复情况及珊瑚羟基磷灰石的体内转归。结果 早期ECT显示在术后2个月内骨再生和再血管化进展顺利，X线和组织学显示术后组织工程骨成骨呈渐进性和偏心性：远期X线和组织学显示组织工程骨与山羊胫骨牢固愈合，并开始塑形且出现髓腔再通，珊瑚羟基磷灰石在体内逐渐成为骨基质的组成成分，自身架构消失。结论 组织工程骨可以完全修复山羊大段负重骨骨缺损，形成正常骨组织并发挥功能；珊瑚羟基磷灰石最终被降解转化成骨基质。

Long-term observation of large weight-bearing bone defect in goats repaired with tissue engineering technique

Objective To observe the long-term effect of tissue engineering-based repair of large weight-bearing bone defect in goats, and the final outcome of the scaffold material coral hydroxyapatite (CHAP) in vivo. Methods Fifteen Chinese goats were subjected to operations to induce a 2-cm left tibial diaphyseal defect, which was filled subsequently with CHAP and bone marrow stromal stem cells (BMSCs). The repaired defects were evaluated by ECT, X-ray and histology in the early stage and at 6, 12, 18, and 24 months postoperatively. Results ECT showed good bone regeneration and revascularization within 2 months postoperatively. X-ray and histology displayed eccentric and gradual bone regeneration in the early stage, and the tissue-engineered bone graft was firmly healed with the goat tibia. X-ray and histological examination at 6, 12, 18, 24 months postoperatively revealed moulding of the new bones and medullary cavity recanalization, and the structure of CHAP disappeared and gradually integrated into the new bones. Conclusions Tissue-engineered bone is capable of total repair of large bone defect in goats by forming normal functional new bones. CHAP can be eventually degraded completely and become the component of the newly generated bones.