Patient-Tailored Selective Laser Melt-Fabricated Plates for Repair of Foot and Ankle Pathology

 描述（由申请人提供）：本项目旨在开发新型、患者特定、几何形状复杂的钛（Ti）合金接骨板，通过增材制造（AM，也称为3D打印）制成，用于足部和踝关节应用。这些接骨板将提供上级固定和机械性能，同时最大限度地减少接骨板体积。足部和踝关节手术很常见，仅在美国每年就有超过20万例拇囊炎修复手术。四肢骨折修复市场预计将达到45亿美元 每年到2017年。目前用于足部和踝部修复的板是简单的，主要具有二维几何形状，其不能很好地符合足部和踝部中骨骼的复杂解剖结构。因此，外科医生花费时间弯曲接骨板以适应患者解剖结构，这并不总能保证充分固定。 所提出的具有定制结构的AM创建的接骨板将通过改善配合、保持强度、减小轮廓和降低成本来促进上级稳定性。通过使用选择性激光熔化钛合金的AM技术，可以根据患者解剖结构定制几何形状，这将实现更好的匹配并缩短手术时间。复杂的结构，如孔隙、内部通道和薄壁部分，将有助于骨生长、优化机械性能和减少软组织刺激。通道也可用作缝线或移植物材料的附着点。此外，AM板的使用降低了与传统制造相关的成本，在传统制造中，模具和工具需要在患者之间更换。 该项目将通过三个具体目标来实现。目标1将通过基于解剖成像的模型有限元分析（FEA）来定制具有复杂3D特征的患者特定F & A接骨板的设计。该目标将通过基于尸体足部解剖成像创建器械的3D模型并评价模型在多种临床负载情况下的性能来实现。目标2将通过比较AM创建的接骨板和传统制造的接骨板的机械性能和生产效率来评估目标1的设计。本目标将确定每种方法的生产成本、时间和浪费，并比较单调和循环加载状态下的机械性能。目标3将评价AM创建的接骨板在目标1中成像的尸体足标本中用于特定病理的拟合和机械性能。该目标通过生产AM创建的接骨板以适应具有不同病理的复杂骨骼来验证先前的目标。将分别通过显微CT和力学测试评价接骨板与骨的贴壁和力学性能。第一阶段的成功完成将展示新型的、患者定制的、AM创建的接骨板，用于治疗足和踝关节病变，可以承受承重条件。这些接骨板将增强固定和稳定性，从而改善临床愈合和融合。

 DESCRIPTION (provided by applicant): The objective of this project is to develop novel, patient-specific, geometrically complex, Titanium (Ti) alloy plates made by additive manufacturing (AM, also called 3D-printing) for foot and ankle applications. These plates will offer superior fixation and mechanical performance, while minimizing the plate bulk volume. Foot and ankle surgeries are common, where over 200,000 are performed each year in the U.S. for bunion repair alone. The market for extremity fracture repair is expected to reach $4.5 Billion annually by 2017. Current plates for foot and ankle repair are simple with mainly two-dimensional geometries, which do not conform well to the complex anatomy of the bones in the foot and ankle. Therefore, surgeons spend time bending plates to fit patient anatomy, which does not always guarantee sufficient fixation. The proposed AM-created plates with tailored architectures will promote superior stability by improving fit, maintaining strength, reducing profile, and reducing cost. By using the AM technique of selective laser melting of Ti alloy, the geometry can be tailored to the patient anatomy, which will achieve better fit and reduce surgery time. Complex architectures, such as pores, internal channels, and thin-walled sections, will aid in bone growth, optimization of mechanical properties, and reduction of soft tissue irritation. Channels can also serve as attachment points for suture or graft material. In addition, the use of AM plates decreases costs associated with traditional manufacturing where molds and tooling would need to be changed between patients. This proposed project will be accomplished through three specific Aims. Aim 1 will tailor the design of patient-specific F&A plates featuring complex 3D features through finite element analysis (FEA) of models based upon anatomic imaging. This Aim will be achieved by creating 3D models of devices based upon cadaveric foot anatomic imaging and evaluating the models' performance under multiple clinical loading scenarios. Aim 2 will assess the designs from Aim 1 by comparing AM-created plates and traditionally manufactured plates for mechanical performance and production efficiency. This Aim will determine the production cost, time, and waste for each method and compare the mechanical performance under monotonic and cyclic loading regimes. Aim 3 will evaluate the fit and mechanical performance of AM-created plates for specific pathologies in the cadaveric foot specimens imaged in Aim 1. This Aim serves to validate the prior Aims by producing AM-created plates to fit complex bones with varying pathologies. The plate to bone apposition and mechanical performance will be evaluated by micro-CT and mechanical testing, respectively. The successful completion of Phase I will demonstrate novel, patient-tailored, AM-created plates for treating foot and ankle pathologies that can sustain load-bearing conditions. These plates will enhance fixation and stability, leading to improved clinical healing and fusion.