Biopolymeric Strength Augmenation to the Spine

生物聚合物增强脊柱强度

• 批准号: 6787514
• 负责人: DAVID D HILE
• 金额: $ 10万
• 依托单位: CAMBRIDGE SCIENTIFIC, INC.
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2004-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6787514
• 关键词: biodegradable product; biomaterial development /preparation; biomechanics; biomimetics; biotechnology; bone prosthesis; bone regeneration; bone transplantation; compression; dicarboxylate; intervertebral disk surgery; mechanical pressure; mechanical stress; medical implant science; osteocytes; osteogenesis; polymers; spinal fusion; tissue engineering; tissue support frame; vertebrae

DESCRIPTION (provided by applicant): Spinal fusion is the most common type of bone grafting procedure. Despite the continuing evolution of devices designed to aid in interbody fusion, nonunion remains problematic. Stability of vertebral segments relies on solid bony fusion across the fusion site. In a typical process, autologous bone, the "gold standard," is used to construct the fusion site. However, the sometimes limited supply of autograft and concerns over the safety of allograft have fueled the search for synthetics. It is the hypothesis of this grant application that a biopolymeric scaffold can add dimensional stability to autograft bone while maintaining the osteoinductive properties of the autograft and supporting the volume and shape of the fusion site. The proposed bone graft substitute is based on the biodegradable polymer poly(propylene fumarate-co-fumaric acid), "PPF." PPF, an unsaturated polyester, can be crosslinked in the presence of effervescent and osteoconductive fillers and cured in situ yielding a porous bone-like scaffold in intimate contact with host tissue. The use of a degradable biopolymeric scaffold could, at least, extend the working volume of autograft without compromising its osteoconductive properties and, at best, improve upon the mechanical and bioactive properties of the grafl material as graft consolidation occurs. This Phase I study will determine if it is feasible to develop a PPF biopolymeric-based bone graft substitute suitable for the support of spinal fusion with feasibility defined as mechanics appropriate for immediate stabilization at placement and then continuing stabilization of the polymer-bone construct over the course of the fusion process concomitant with the maintenance of a porosity permissive for cellular ingrowth PPF-based test materials will be evaluated in vitro based upon these initial and temporal morphological and mechanical outcomes in both static and dynamic modes. The formulation that best meets these Phase I in vitro outcomes will be evaluated in vivo in Phase II to evaluate osteointegration and stability using biomechanical histological, and histomorphometric techniques.

描述（由申请人提供）：脊柱融合是最常见的骨移植手术类型。尽管旨在帮助椎间融合的设备不断发展，骨不连仍然是个问题。椎骨节段的稳定性依赖于融合部位的牢固骨融合。在典型的过程中，自体骨（“黄金标准”）用于构建融合部位。然而，有时自体移植物的供应有限以及对同种异体移植物安全性的担忧推动了对合成物的寻找。本拨款申请的假设是生物聚合物支架可以增加自体移植骨的尺寸稳定性，同时保持自体移植物的骨诱导特性并支持融合部位的体积和形状。所提出的骨移植替代物基于可生物降解的聚合物聚（富马酸丙烯酯-共富马酸）“PPF”。 PPF 是一种不饱和聚酯，可以在泡腾和骨传导填料存在下交联，并在原位固化，产生与宿主组织紧密接触的多孔骨状支架。使用可降解的生物聚合物支架至少可以扩大自体移植物的工作体积而不损害其骨传导性能，并且最多可以在移植物固结发生时改善移植物材料的机械和生物活性性能。 该第一阶段研究将确定开发一种适用于支持脊柱融合的 PPF 生物聚合物骨移植替代品是否可行，其可行性定义为适合在放置时立即稳定，然后在植入物上持续稳定聚合物骨结构的力学。融合过程的过程以及维持细胞向内生长允许的孔隙率的维持基于 PPF 的测试材料将根据静态和动态模式下的这些初始和时间形态和机械结果在体外进行评估。最能满足这些 I 期体外结果的配方将在 II 期体内进行评估，以使用生物力学组织学和组织形态计量技术评估骨整合和稳定性。