Peck Jonathan H, Sing David C, Nagaraja Srinidhi, Peck Deepa G, Lotz Jeffrey C, Dmitriev Anton E
U.S. Food and Drug Administration, Center for Devices and Radiological Health, Office of Device Evaluation, Division of Orthopedic Devices, Silver Spring, MD 20993, USA.
University of California at San Francisco, Department of Orthopedic Surgery, San Francisco, CA 94143, USA; U.S. Food and Drug Administration, Center for Devices and Radiological Health, Office of Science and Engineering Laboratories, Division of Applied Mechanics, Silver Spring, MD 20993, USA.
J Biomech. 2017 Mar 21;54:26-32. doi: 10.1016/j.jbiomech.2017.01.032. Epub 2017 Feb 1.
Cervical intervertebral body fusion devices (IBFDs) are utilized to provide stability while fusion occurs in patients with cervical pathology. For a manufacturer to market a new cervical IBFD in the United States, substantial equivalence to a cervical IBFD previously cleared by FDA must be established through the 510(k) regulatory pathway. Mechanical performance data are typically provided as part of the 510(k) process for IBFDs. We reviewed all Traditional 510(k) submissions for cervical IBFDs deemed substantially equivalent and cleared for marketing from 2007 through 2014. To reduce sources of variability in test methods and results, analysis was restricted to cervical IBFD designs without integrated fixation, coatings, or expandable features. Mechanical testing reports were analyzed and results were aggregated for seven commonly performed tests (static and dynamic axial compression, compression-shear, and torsion testing per ASTM F2077, and subsidence testing per ASTM F2267), and percentile distributions of performance measurements were calculated. Eighty-three (83) submissions met the criteria for inclusion in this analysis. The median device yield strength was 10,117N for static axial compression, 3680N for static compression-shear, and 8.6Nm for static torsion. Median runout load was 2600N for dynamic axial compression, 1400N for dynamic compression-shear, and ±1.5Nm for dynamic torsion. In subsidence testing, median block stiffness (Kp) was 424N/mm. The mechanical performance data presented here will aid in the development of future cervical IBFDs by providing a means for comparison for design verification purposes.
颈椎椎间融合器（IBFDs）用于在颈椎病变患者发生融合时提供稳定性。对于制造商在美国销售新型颈椎IBFD，必须通过510(k)监管途径证明其与先前已获美国食品药品监督管理局（FDA）批准的颈椎IBFD具有实质等同性。机械性能数据通常作为IBFDs的510(k)流程的一部分提供。我们回顾了2007年至2014年期间所有被认为具有实质等同性并获批上市的颈椎IBFD的传统510(k)申报文件。为减少测试方法和结果中的变异性来源，分析仅限于无集成固定、涂层或可扩展特征的颈椎IBFD设计。对机械测试报告进行了分析，并汇总了七项常用测试（按照ASTM F2077进行的静态和动态轴向压缩、压缩剪切和扭转测试，以及按照ASTM F2267进行的下沉测试）的结果，并计算了性能测量的百分位数分布。八十三（83）份申报文件符合纳入本分析的标准。静态轴向压缩时，器械的屈服强度中位数为10117N，静态压缩剪切时为3680N，静态扭转时为8.6Nm。动态轴向压缩时，跳动载荷中位数为2600N，动态压缩剪切时为1400N，动态扭转时为±1.5Nm。在下沉测试中，块体刚度（Kp）中位数为424N/mm。本文提供的机械性能数据将通过提供一种用于设计验证目的的比较方法，有助于未来颈椎IBFD的开发。
