骨相关疾病是严重危害人类健康和生活质量的重大疾病，对不规则形状的骨缺损进行修复一直是临床一种比较常见的骨科疾病需要解决的问题之一。临床上主要是采用自体骨、异体骨或活性仿生生物材料在缺损部位进行修复重建，以部分或全面恢复缺损区域组织功能，减轻患者痛苦并提高生活质量，而采用自体或异体骨移植会面临增加创伤、供体有限、疾病传染或免疫排斥等风险。本项目拟采用一种生物相容性好、且体内降解速度可控的温度敏感水凝胶作为骨生长活性因子的载体，并与胶原纤维和活性磷酸钙盐复合得到可注射的多组分活性骨修复材料，用于动物脊柱后柱不规则骨缺损修复重建实验，并评价该复合体系在骨组织重建中的原位引导/诱导成骨作用。通过本项目实施我们将建立制备可体内外注射的温度敏感型水凝胶（PEG-PCL-PEG）的平台技术、通过纳米技术解决活性蛋白药物缓控释的平台技术和可注射纳米复合物的平台技术，为解决脊柱术后不规则缺损重建奠定基础。

Bone related diseases are a kind of serious diseases in clinical field, which have significant effect on peoples' health and life quality. Repairing the bone defects with irregular shape is still a problem of orthopedics to be solved. In particular, recovering of defects in vertebral plate, spinous process and zygapophysis, is one needful follow-up treatment in spine surgery. In clinical practice, the defect sites are usually reconstructed by implanting autologous, allogenic bone or active biomaterials to recover tissue functions, thus alleviate patients' pain and improve their life qualities. However, implanting autologous or allogenic bone may face various risks such as increased wounds, limited donor, disease infection, immunological rejection,and etc.Therefore, in this project, we will use biodegradable and biocompatible thermo-sensitive hydrogel as a carrier to delivery bioactive bone growth factor, and then combine it with collagen fibers and calcium phosphate to prepare an injectalbe multi-component hydrogel composites to repaire the irregular bone defects. Such injectable hydrogel system will be used to repair the spinal defects in rabbits, and its capacity of guided bone regeneration in situ will be evaluated simultaneously. Our goal in this study is to establish a platform technology of fabricating a novel biodegradable thermo-sensitive PECE hydrogel which can be injected in vivo and cleared from the body under control, a technology of achieving controlled release of bioactive protein drugs through nanotechnology. We hope that our project could play a solid foundation to develop novel biomaterial for repairing irregular bone defects,and provide idea or perspective for choosing suitable biomaterials to reconstruct bone defects after spine surgery.