Failure Mechanisms of Joint Replacement

关节置换的失效机制

• 批准号: 7173019
• 负责人: Joan E Bechtold
• 金额: $ 24.03万
• 依托单位: HENNEPIN HEALTHCARE RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-08-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7173019
• 关键词: 3-Dimensional; Address; Allografting; Anisotropy; Area; Aspirate substance; Biomedical Engineering; Blood Platelets; Bone Growth; Bone Marrow; Bone Transplantation; Cells; Clinical; Collaborations; Devices; Effectiveness; Experimental Models; Failure; Frequencies; Funding; Future; Glycocalyx; Goals; Growth; Growth Factor; Human; Hydroxyapatites; IGF1 gene; Implant; Improve Access; Insulin-Like Growth Factor I; Longevity; Marrow; Measures; Mechanics; Modeling; Morphology; Numbers; Operative Surgical Procedures; Outcome Measure; Performance; Plasma; Poly (RGD); Polymethyl Methacrylate; Procedures; Process; Replacement Arthroplasty; Research Personnel; Scientist; Structure; Surface; Techniques; Thick; Tissues; Titanium; Weight; Work; base; bone; coralline hydroxyapatite; density; implant coating; improved; indexing; poly(DL-lactide); programs; sample fixation; success

DESCRIPTION (provided by applicant): Our long-term goal is to improve the clinical success of revision joint replacements. In our original application, we developed an experimental model of the revision implant setting. The model uses our established weight-loaded micromotion device, to engender a revision cavity with a tissue morphology representing an aseptically loosened human implant. At revision surgery, the pistoning PMMA implant is replaced with a prescribed implant/graft treatment. In our earlier work, we identified diminished osteogenic performance as a major deficit of revision implants, and we identified the relatively impermeable sclerotic bone (SB) rim that forms during the process of aseptic loosening as a major factor in this poorer fixation. We focus on this devitalized sclerotic bone rim since fixation in the sclerotic region is known to be critical clinically for achieving overall stability of a revision implant. We have successfully shown that cracking (perforating) the sclerotic bone rim improved revision fixation 5-7 fold. Addition of bone graft increased fixation up to 40 fold, and, with rim cracking, hydroxyapatite (HA) implants had superior fixation to their titanium (Ti) counterparts. Graft improved fixation in all settings investigated. We will study hypotheses addressing three Aims, based on promising results from the prior funding period. Aim 1: to provide greater access (of native growth factors, cells, marrow) to the revision interface by perforating (cracking) the sclerotic bone rim. We will compare rim cracking to the procedure of reaming to remove the SB rim. Aim 2: to improve utilization of native growth factors and cells by coatings encouraging bone growth directly on the revision implant surface. Aim 3: to augment the revision interface with local application of bone graft and bone graft substitutes, with and without bone marrow aspirate and platelet rich plasma (PRP) concentrates. For Aim 1, the two access techniques studied are rim cracking and reaming. For Aim 2, the three revision implant coatings studied are Ti, HA + RGD and Poly, D, Lactide (PLDDA) (with TGFb1 and IGF1). For Aim 3, the four augmentations studied are allograft, coralline hydroxyapatite, with and without marrow aspirate and PRP. Sixteen paired groups of these treatments will determine effectiveness, interactions and synergies of treatments. Outcome measures are histomorphometric (% bone area and implant contact in zones, and connectivity) micro-CT (including bone volume, surface to volume ratio, anisotropy index), and mechanical (static pushout strength, stiffness, energy, and dynamic damping factor and damping odulus). Our active partnership of an accomplished clinician scientist and his team, and bioengineers and scientists bring a diverse set of competencies working towards our common goal. Our good collaborations and established and clinically verified experimental model is a strong base for future studies to improve the longevity of clinically vexing revision implants.

描述（由申请人提供）：我们的长期目标是提高翻修关节置换术的临床成功率。在我们最初的应用中，我们开发了修复种植体设置的实验模型。该模型使用我们建立的负重微动装置来产生修正腔，其组织形态代表无菌松动的人体植入物。在修复手术中，活塞式 PMMA 植入物被指定的植入物/移植物治疗所取代。在我们早期的工作中，我们发现成骨性能下降是修复种植体的主要缺陷，并且我们发现在无菌松动过程中形成的相对不可渗透的硬化骨（SB）边缘是这种固定效果较差的主要因素。我们关注的是这种失活的硬化骨边缘，因为众所周知，硬化区域的固定在临床上对于实现翻修种植体的整体稳定性至关重要。我们已成功证明，打碎（穿孔）硬化骨边缘可将修正固定提高 5-7 倍。添加骨移植物将固定效果提高了 40 倍，而且，即使边缘开裂，羟基磷灰石 (HA) 植入物的固定效果也优于钛 (Ti) 植入物。在所有调查的环境中，移植物均改善了固定。我们将根据上一个资助期的有希望的结果，研究解决三个目标的假设。目标 1：通过穿孔（破裂）硬化骨边缘，为翻修界面提供更多通道（天然生长因子、细胞、骨髓）。我们将轮辋开裂与铰孔去除 SB 轮辋的过程进行比较。目标 2：通过涂层直接促进修复种植体表面上的骨生长，提高天然生长因子和细胞的利用率。目标 3：通过局部应用骨移植和骨移植替代物（使用或不使用骨髓抽吸物和富血小板血浆 (PRP) 浓缩物）来增强翻修界面。对于目标 1，研究的两种进入技术是边缘开裂和铰孔。对于目标 2，研究的三种修复种植体涂层是 Ti、HA + RGD 和聚 D、丙交酯 (PLDDA)（含有 TGFb1 和 IGF1）。对于目标 3，研究的四种增强方法是同种异体移植、珊瑚羟基磷灰石、有或没有骨髓抽吸物和 PRP。这些治疗的十六对组将确定治疗的有效性、相互作用和协同作用。结果测量包括组织形态测量（%骨面积和区域内种植体接触以及连接性）、微CT（包括骨体积、表面积与体积比、各向异性指数）和机械（静态推出强度、刚度、能量和动态阻尼系数和阻尼模量）。我们由一位卓有成就的临床科学家及其团队、生物工程师和科学家组成的积极合作伙伴关系，为我们的共同目标带来了多种能力。我们良好的合作以​​及已建立并经过临床验证的实验模型为未来的研究奠定了坚实的基础，以提高临床上令人烦恼的翻修种植体的使用寿命。