TISSUE STRAIN MAGNITUDE EFFECTS ON BONE INGROWTH

组织应变大小对骨长入的影响

• 批准号: 2082349
• 负责人: Scott J Hollister
• 金额: $ 18.32万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-09-30 至 1998-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2082349
• 关键词: biomaterial compatibility; biomechanics; bone regeneration; collagen; dogs; implant; osteoclasts; osteogenesis; physiologic bone resorption; scanning electron microscopy; single photon emission computed tomography

DESCRIPTION (adapted from the applicant's Abstract): This application proposes studies which address the problem of suboptimal fixation of porous coated implants due to poor bone ingrowth. Two specific aims are described. The first is to determine if different initial interface strains produce different amounts of bone ingrowth. The second is to determine if interface tissue adapts to limit strains within a range of 200 to 2500 microstrain as has been proposed for cortical bone. The recent development of an homogenization sampling procedure by the applicant provides the capability for estimating tissue strains realistically for the first time. The technique, combined with a unique, well-established canine model system which allows controlled implant loads to be applied to exposed trabecular bone of the canine distal femur, will be used to test the hypothesis that interface tissue adapts to limit strain within a homeostatic range. Three different groups of animals will be subjected to three different magnitudes of loading, ranging from 0 to 8 pounds. The animals will be sacrificed at 6 months post surgery and bone cores will be obtained. Type I pro- collagen and osteoclast resorption will be measured in the experimental limb and compared to the contralateral limb to determine how close the bone is to being at equilibrium. Backscattered scanning electron microscopy (SEM) will be used to construct a 3-D digitized image of the ingrowth in each platen region. Micro-computed tomography (micro-CT) will be used to quantify bone architectural changes. Images from both SEM and micro-CT will be used to construct 3-D microstructural finite element models of the implant tissue interface and the surrounding bone. Tissue level strains will be estimated using the homogenization sampling procedure and used to test the hypotheses concerning tissue adaptation. If trabecular bone tissue does adapt to exist within a homeostatic strain range, this would provide criteria for designing porous coated implant interfaces that may achieve better bone ingrowth fixation.

描述（改编自申请人的摘要）：本申请 提出了解决固定不理想问题的研究 由于骨向内生长不良而导致多孔涂层种植体。 两个具体目标是 描述的。 首先是判断初始界面是否不同 菌株产生不同量的骨向内生长。 第二个是 确定界面组织是否适应限制在一定范围内的应变 为皮质骨建议的 200 至 2500 微应变。 这 最近开发的均质化抽样程序 申请人提供了估计组织应变的能力 第一次真正地。 该技术结合了 独特、完善的犬类模型系统，允许受控 将植入物负载施加到犬科动物暴露的骨小梁上 股骨远端，将用于检验界面组织的假设 适应将应变限制在稳态范围内。 三种不同 动物群体将受到三种不同程度的影响 负载范围为 0 至 8 磅。 动物将被处死于 术后6个月，将获得骨芯。 I 型亲 胶原蛋白和破骨细胞的吸收将在实验中测量 与对侧肢体进行比较，以确定肢体的接近程度 骨骼处于平衡状态。 背散射扫描电子 显微镜 (SEM) 将用于构建 3D 数字化图像 每个压板区域向内生长。 微型计算机断层扫描 (micro-CT) 将用于量化骨骼结构的变化。 两者的图像 SEM 和 micro-CT 将用于构建 3D 微观结构有限 种植体组织界面和周围骨骼的元素模型。 将使用均质化采样来估计组织水平应变 程序并用于检验有关组织适应的假设。 如果骨小梁组织确实适应了体内平衡 应变范围，这将为设计多孔涂层提供标准 可以实现更好的骨向内生长固定的种植体界面。