Lattice materials with graded mechanical properties for the development of a novel hip-replacement implant

平均而言，髋关节置换术的寿命为15-20年，之后需要进行翻修手术。翻修手术是不可取的，有问题的，比初次置换术更不成功。问题是当前植入物的能力不足以保持宿主骨的质量，因此不能将翻修植入物充分固定到位。本研究项目的目的是为全髋关节置换术植入物开发一种新型材料微结构，该材料微结构可以持续更长时间，保持宿主骨的质量，并提供稳定的植入物固定。申报材料是一种钛合金Ti-6AL-4V，网格;其突破性的特点在于材料性能的受控梯度，旨在匹配骨的局部性能，提供前所未有的弹性和强度性能以及上级抗疲劳性、抗损伤性和耐磨性。新的植入物将加强对需要初次和翻修髋关节置换术的患者的治疗，降低翻修手术的需求和相关的医疗费用;在翻修手术的情况下，它将提高其成功率。 虽然长期目标是使植入物市场做好准备，但具体的短期目标集中在晶格材料设计的模型和方法的开发上，然后进行实验验证。预期结果包括：1）开发多尺度模型，用于表征适用于组织骨支架的网格单元拓扑结构的弹塑性、强度和疲劳特性; 2）对由分级网格材料制成的股骨柄和髋臼杯进行多目标优化，以实现最小磨损、骨吸收和植入物-骨微动。 这项研究将培养一批高素质的研究人员，他们在晶格材料、多尺度力学、生物力学、生物医学工程、设计优化和疲劳测试方面拥有尖端的跨学科专业知识。毕业后，这些学生将刺激加拿大整形外科公司的发展和形成，这将为加拿大创造就业机会和经济利润。

On average, hip-replacements have a life span of 15-20 years, after which revision surgery is necessary. A revision surgery is undesirable, problematic and less successful than a primary replacement. Problematic is the inadequate capacity of current implants to preserve the quality of the host bone, which thus cannot sufficiently secure the revision implant into position. The aim of this research program is to develop a novel material microstructure for a total hip arthroplasty implant which can last longer, maintain the quality of the host bone, and provide a stable implant fixation. The proposed material is a titanium alloy, Ti-6AL-4V, lattice; its groundbreaking hallmark lies in the controlled gradients of material properties which are designed to match the local properties of the bone and provide unprecedented elastic and strength properties as well as superior fatigue, damage and wear resistance. The new implant will enhance the treatment of patients requiring primary and revision hip replacement, lower the need of revision surgery and the related health care cost; in case of revision surgeries, it will increase its success rate. While the long-term vision is to make the implant market ready, the specific short-term goals focus on the development of models and methods for lattice material design, followed by their experimental validation. The anticipated outcomes include 1) the development of multiscale models for the characterization of the elastoplastic, strength and fatigue properties of lattice cell topologies suitable for tissue bone scaffolding; 2) the multiobjective optimization of the femoral stem and acetabular cup made of graded lattice materials for minimum wear, bone resorption and implant-bone micromotion. This research will train a pool of highly qualified researchers equipped with cutting-edge, interdisciplinary expertise in lattice materials, multiscale mechanics, biomechanics, biomedical engineering, design optimization and fatigue testing. Upon graduation these students will stimulate the growth and formation of Canadian companies in the orthopaedic sector, which will result in the creation of jobs and economic profits for Canada.