3D打印个体化股骨短柄的优化设计及临床前研究

Total hip arthroplasty (THA) is the golden standard in the treatment of end-stage degenerative joint disease of the hip. From cemented stem to uncemented femoral stem, especially the advent of the recently hot-debated short stem, adult reconstruction surgeons are pursuing the preservation of proximal femoral bone stock and fully restoration of hip function, rather than just long-term fixation. Short stem femoral component can effectively preserve adjacent bone stock, reduce incidence of thigh pain, optimize stress distribution, avoid proximal-distal mismatch, facilitate minimally invasive surgeries and potential hip revision surgeries. However, stem shortening may induce malposition and unstable fixation that leads to early implant loosening. Three-dimensional anatomical study regarding proximal femurs and medullary canals among Chinese will be performed to identify the modular and patient-specific factors for the design of patient-specific short stem. Along with electron beam melting technology, a custom-designed software, integrating measurement and stem design functions, will be developed to accelerate the overall manufacturing processes of patient-specific short stem. Finally, an optimized protocol regarding the design and manufacture of patient-specific short stem can be determined by evaluating fit and fill, initial stability and stress distribution of femoral stems with varying lengths and designs, and by comparing the distribution of internal defects and fatigue property of stems produced by different manufacturing and post-processing techniques. The research and development of patient-specific short stem can potentially improve fit and fill between the stem and proximal femoral medullary canal, avoid stem malposition, and provide more favorable initial stability and more physiological stress distribution, which can secure long term fixation. In addition, the current study can also provide preliminary data for the research and development of over-the-shelf short stem with high quality for Chinese patients.

人工全髋关节置换术是治疗终末期髋关节疾患的金标准。从骨水泥柄到非骨水泥柄，直至近期热点短柄，关节外科不仅追求假体的长期生存，也追求骨量保护及患髋功能优化。短柄可充分保留骨量，缓解大腿痛，优化应力传递，避免假体远近段不匹配，便于施行微创手术及未来翻修，但其初始稳定性相对下降，且易出现位置不良，长期存留存在隐患。本研究通过股骨及髓腔三维测量，明确个体化短柄设计的个体化及模块化要素；自主研发测量、设计一体化专科软件，联合电子束熔融金属3D打印技术，优化设计及制造流程；系统评估不同柄长及形态股骨柄的匹配填充、初始稳定、应力传递情况，对比设计、加工及热处理技术对股骨柄内部缺陷分布及疲劳性能的影响，最终确定个体化短柄设计、制造的优选方案。个体化短柄通过优化对髓腔的匹配和填充，避免位置不良，提高初始稳定性，优化应力传递，保证假体长期生存，有望为进一步研发适合中国人群的高性能常规短柄假体提供数据支持。

人工全髋关节置换术是治疗终末期髋关节疾患的金标准。从骨水泥柄到非骨水泥柄，直至近期热点短柄，关节外科不仅追求假体的长期生存，也追求骨量保护及患髋功能优化。短柄可充分保留骨量，缓解大腿痛，优化应力传递，避免假体远近段不匹配，便于施行微创手术及未来翻修，但其初始稳定性相对下降，且易出现位置不良，长期存留存在隐患。本研究通过股骨及髓腔三维测量，明确个体化短柄设计的个体化及模块化要素；自主研发测量、设计一体化专科软件，联合电子束熔融金属3D打印技术，优化设计及制造流程；系统评估不同柄长及形态股骨柄的匹配填充、初始稳定、应力传递情况，对比设计、加工及热处理技术对股骨柄内部缺陷分布及疲劳性能的影响，最终确定个体化短柄设计、制造的优选方案。本项目聚焦个体化股骨短柄的设计，自主完成辅助股骨侧重建的图像分割、测量及规划的一体化软件系统的研发；涵盖股骨近段三维解剖轮廓及内部有效髓腔的分析，挖掘个体化股骨短柄的设计要点，不仅需要保证个体化股骨短柄与股骨近端髓腔的形似，达到完美匹配，还需要保证股骨颈前倾角、偏心距、颈干角及股骨头高度与个体局部解剖结构的完美复现；同时，通过摸索3D金属打印的工艺及后处理，改善股骨短柄机械性能，突破疲劳性能不佳这一瓶颈。截止目前，发表论文9篇，其中SCI论文7篇，授权发明专利2项，授权实用新型专利2项，软件著作权3项，获奖2项，转化成果1项，转化金额110万。上述成果不仅有助于改良个体化股骨柄的设计，优化股骨柄与个体髓腔的匹配，有助于完美复制个体的髋关节生物力学环境；一个准确规划安装的股骨柄是髋关节联合规划的核心要素之一，是实践联合前倾角理论中股骨优先原则的先决条件，也是实现真正的个体化规划的前提。个体化短柄通过优化对髓腔的匹配和填充，避免位置不良，提高初始稳定性，优化应力传递，保证假体长期生存，有望为进一步研发适合中国人群的高性能常规短柄假体提供数据支持。