3D打印导航模板精准注射变刚度成血管骨水泥个体化治疗股骨头坏死塌陷的研究

The therapeutic effect of core decompression combined with implanting different kinds of biological or biomimetic materials is not good in treating osteonecrosis of the femoral head when articular surface collapses. And eventually joint function will be lost. Our previous studies suggest that the accurate positioning of focus area is crucial in core decompression, and it plays an important role in treating the necrosis collapse that a moderate and in-time mechanical support been made in the subsidence area. If the local mechanical changes of each necrosis focus can be individually analyzed and the biological materials that meets the biomechanical demands of subsidence area can be manufactured and implanted back to the matching area precisely, it expected to improve the effect of treating osteonecrosis and collapse of the femoral head. We carried out a research which include computer three-dimensional modeling and stress analysis of the subsidence area, then we simulated the surgery and manufactured the guide template for injection through 3D print technique. We rebuilt the normal biomechanical environment of the subsidence area and provided adequate mechanical support for the femoral head cartilage in subchondral bone area through injecting the inject angiogenesis activated injectable composite calcium phosphate cement precisely into the specific spot in subsidence area. The elasticity modulus of the cement was calculated based on preliminary data analysis. This injection is aim to treat the collapse of the femoral head necrosis. It is the study on manufacturing technique of angiogenesis activated variable stiffness calcium phosphate cement that provides theoretical basis for personalized treatment of osteonecrosis and collapse of the femoral head and reconstruction of bionic structure in the critical area.

股骨头坏死关节面塌陷时，髓芯减压联合局部植入各种生物或仿生材料治疗效果不佳，最终关节功能丧失。前期研究结果表明，髓芯减压手术中，病灶的精准定位至关重要，塌陷区适时、适度的机械支撑在坏死塌陷中起关键作用。如果可以个体化分析计算每个坏死病灶局部的力学变化，制造符合塌陷区力学要求的生物材料，准确定位、回植到匹配区域，做到生物力学的仿生回植，有望提高股骨头坏死塌陷的治疗效果。本研究拟对坏死塌陷区进行计算机三维建模、应力分析、模拟手术、通过3D打印技术制造注射导航模板，将不同弹性模量的成血管活性可注射复合磷酸钙骨水泥依据前期分析数据精准注射至塌陷区特定区域，恢复塌陷区正常生物力学环境，在软骨下骨区域为股骨头软骨提供充足且合理的力学支撑，以求治疗股骨头坏死塌陷。研究变刚度成血管活性可注射复合磷酸钙骨水泥制造工艺，为个体化治疗股骨头塌陷并在股骨头的关键性区域进行仿生结构的重建提供理论基础。

股骨头坏死关节面塌陷时，髓芯减压联合局部植入各种生物或仿生材料治疗效果不佳，最终关节功能丧失。前期研究结果表明，髓芯减压手术中，病灶的精准定位至关重要，塌陷区适时、适度的机械支撑在坏死塌陷中起关键作用。如果可以个体化分析计算每个坏死病灶局部的力学变化，制造符合塌陷区力学要求的生物材料，准确定位、回植到匹配区域， 做到生物力学的仿生回植，有望提高股骨头坏死塌陷的治疗效果。本研究主要研究了以下三方面内容：① 人体尸骨的3D导航模板辅助下髓芯减压的精准性的检测；② 对不同改进术式的髓芯减压术治疗后的病人的股骨进行有限元分析，分析术后的应力分布情况，并相互之间对比，看不同改进术式对生物力学的影响；③ 进一步优化了股骨头三维模型重建及力学分析，并且在骨水泥制备方面取得了进展。此外，在本项目支持下扩展研究了：①严重膝非感染性关节炎合并股骨髁上骨折的高龄患者，一期膝关节置换同时治疗终末期关节炎及股骨髁上骨折的可行性；②激素诱导下成骨细胞中应力蛋白PIEZO1的表达变化及其功能机制研究；③单髁置换治疗单冲膝关节内侧间室骨关节炎的短期疗效等。得出以下重要结果：ａ．髓芯减压术前模拟，即通过计算机软件模拟髓芯减压术获取髓芯减压术的参数如减压通道深度、角度等，并以此参数为参考可以实现以最小的创伤、以最小的减压范围实现快速、精准的清除不规则病变股骨头坏死灶，对术前髓芯减压的评估、术后髓芯减压塌陷的预测有着重要的临床指导意义，为进一步实现实体手术提供理论基础；ｂ．计算机-快速成型辅助模拟髓芯减压在股骨的应用，即将计算机技术与快速成型技术结合起来模拟髓芯减压术，其平均距离为误差为1.92mm，基本达到临床精准髓芯减压的要求，该方法在股骨的应用显示了其对实现精准坏死病灶的清除髓芯减压治疗股骨头坏死，及以期获得更好疗效提供了一种新的方法。