3D Printed Silicon Nitride Porous PEEK Composite Spinal Cages for Anti-Infection

项目总结 脊柱融合术是持续性颈部和背部疼痛的标准治疗方法，但用于固定的硬件 这种融合可能携带甚至促进细菌，这些细菌会导致成本高昂的持续、难以治疗的感染。 并损害病人的健康。在可用于脊柱融合的材料中，聚醚醚酮(PEEK) 笼子因其强度、生物兼容性和辐射透明度而脱颖而出，但像其他材料一样，它们 易受脊椎感染的。氮化硅(Si3N4)间隔物已被用于其他脊椎应用，其中 他们因感染引起的可报告不良事件的比率远低于行业标准，但事实并非如此 由于其潜在的下沉和脆性骨折，是稳定脊柱融合的理想选择。要解决这个问题 挑战，SINTX利用第一阶段SBIR资金开发和测试了一种3D打印的Si3N4-PEEK材料 将Si3N4的抗菌和骨整合性能与PEEK的强度和弹性结合在一起。 在这个第二阶段的SBIR中，SINTX建议使用这种材料来开发3D打印的抗微生物脊柱融合术 框架，促进骨整合，承受活体负荷，并促进成像。该项目包括 正常和污染的长期生物力学性能和体内融合性能测试 操作场景。这些活动的成功完成将使SINTX准备510(K)投放市场 食品药品监督管理局的通知申请。SINTX预计3D打印设备将进一步开发和商业化 Si3N4-PEEK脊柱融合器将为骨科医生提供一种高性能的融合设备，可以 大大降低了融合相关感染的发生率。 目标1.通过正式的设计和工艺风险将潜在的设计和制造风险降至最低 按照国际标准化组织14971标准进行管理分析。里程碑：完成设计FMEA和 按照国际标准化组织14971标准进行FMEA过程，以最大限度地减少与新型颈椎保持架和冷冻设计相关的风险。 目的2.验证完成的3DP Si3N4-PEEK颈椎保持架满足静态和疲劳载荷 ASTM F2077的要求和ASTM F2267的沉降要求。里程碑：遵循 在目标1中设计冻结，展示静态和疲劳压缩、剪切、扭转强度和下沉。 最终完成的3DP Si3N4-PEEK多孔笼的阻力达到或超过颈椎保持架指南 由ASTM F2077和ASTM F2267建立，并在文献中作为许多保持架制造商的基准。 目的3.测定抗菌活性(实验臂)和体内生物相容性 3DP Si3N4-PEEK颈椎融合器的骨整合(生物相容性GLP臂) 颈椎融合术。里程碑：最终、包装和验证的植入物将通过国际标准化组织10993的要求。 3DP Si3N4-PEEK植入物将具有生物相容性、骨向内生长、融合和抗感染能力 与对照组3DP PEEK椎间融合器相当或更好。

PROJECT SUMMARY Spinal fusion is the standard treatment for persistent neck and back pain, but the hardware used to stabilize the fusion can harbor or even promote bacteria that lead to persistent, difficult-to-treat infections that are costly and damaging to patient health. Among the available materials for spinal fusion, polyether-ether-ketone (PEEK) cages stand out due to their strength, biocompatibility, and radiolucency, but like other materials, they are susceptible to spinal infections. Silicon nitride (Si3N4) spacers have been used in other spinal applications where their rates of reportable adverse events due to infection are much lower than industry norms, but they are not ideal for stabilizing spinal fusions due to their potential for subsidence and brittle fracture. To address this challenge, SINTX used Phase I SBIR funding to develop and test a 3D-printed Si3N4-PEEK material that incorporates the antimicrobial and osseointegrative properties of Si3N4 with the strength and elasticity of PEEK. In this Phase II SBIR, SINTX proposes to use this material to develop a 3D-printed anti-microbial spinal fusion cage that promotes osseointegration, withstands in vivo loading, and facilitates imaging. The project includes long-term biomechanical performance and in vivo fusion property testing in both normal and contaminated operative scenarios. Successful completion of these activities will position SINTX to prepare a 510(k) premarket notification application for FDA. SINTX anticipates further development and commercialization of a 3D-printed Si3N4-PEEK spinal fusion cage will provide orthopedic surgeons a high-performance fusion device that could greatly reduce the incidence of fusion-associated infections. Aim 1. Minimize potential design and manufacturing hazards by formal design and process risk management analyses in accordance with ISO 14971. Milestone: Completion of the design FMEA and process FMEA per ISO 14971 to minimize risks associated with the novel cervical cages and design freeze. Aim 2. Verify that the finalized 3DP Si3N4-PEEK cervical cage meets the static and fatigue loading requirements of ASTM F2077 and subsidence requirements of ASTM F2267. Milestone: Following the design freeze in Aim 1, demonstrate static and fatigue compression, shear, and torsion strength and subsidence resistance of the finalized 3DP Si3N4-PEEK’s porous cage meets or exceeds the guidelines for cervical cages established by ASTM F2077 and ASTM F2267 and benchmarked for many cage manufacturers in the literature. Aim 3. Determine antimicrobial activity (experimental arm) and in vivo biocompatibility and osteointegration (biocompatibility GLP arm) for a 3DP Si3N4-PEEK cervical cage in a caprine model of cervical spinal fusion. Milestone: Final, packaged, and validated implants will pass requirements in ISO 10993. 3DP Si3N4-PEEK implants will have biocompatibility, bone ingrowth, fusion, and resistance to infection comparable to or better than control 3DP PEEK spinal cages.