Department of Orthopedics, Huashan Hospital, Fudan University, No.12 Wulumuqi Middle Road, Shanghai, China.
Department of Research & Tech, Medtronic Greater China Co., Ltd., Block 11, No. 3000 Long Dong Avenue, Pudong, Shanghai, China.
Biomed Res Int. 2018 Nov 25;2018:7961509. doi: 10.1155/2018/7961509. eCollection 2018.
Bioabsorbable Mg-based implants were previously assessed due to their intrinsic advantages, but Mg-based cage related research is limited. The specific blood supply and stress of the intervertebral environment can affect the function of Mg-based implants. The objective of this study was to investigate the performance of a bioabsorbable Mg-Zn alloy cage in anterior cervical discectomy and fusion (ACDF) and evaluate the control of degradation of the Mg-Zn cage surface modified by microarc oxidation (MAO) technology containing Si under an intervertebral microenvironment.
Twenty-four goats were divided into four groups according to the experimental period and all underwent ACDF at C2-3 and C4-5 with porous Mg-Zn cage covered with a MAO/Si-containing coating in one intervertebral space and with autologous iliac bone in another space. After 3, 6, 12, or 24 weeks after operation, the cervical spine specimens were harvested to evaluate the biocompatibility, fusion status, and degradation conditions using blood analysis, radiology, biomechanical testing, histology, and micro-CT.
The Mg-Zn cages showed ideal biocompatibility and biomechanical characterization; however, the fusion state, as evaluated with radiology and histology, was not acceptable. Modified by the MAO/Si-containing coating, the degradation rate of the Mg-Zn cages was controllable but slower than expected.
MAO/Si-containing coating Mg-Zn alloy cages demonstrated excessive control of degradation and fusion failure after 24 weeks postoperatively. We conclude that further studies should be designed to improve the using of Mg-based materials at the intervertebral space.
先前评估了可生物吸收的 Mg 基植入物，因为它们具有内在优势，但有关 Mg 基笼的研究有限。 椎间环境的特定血液供应和应力会影响 Mg 基植入物的功能。 本研究的目的是研究可生物吸收的 Mg-Zn 合金笼在前路颈椎间盘切除术和融合术（ACDF）中的性能，并评估微弧氧化（MAO）技术表面改性的 Mg-Zn 笼在椎间微环境下 Si 的降解控制。
根据实验期，将 24 只山羊分为四组，每组均在 C2-3 和 C4-5 进行 ACDF，一个椎间空间覆盖有 MAO/Si 涂层的多孔 Mg-Zn 笼，另一个空间覆盖有自体髂骨。 在术后 3、6、12 或 24 周时，收获颈椎标本，通过血液分析、放射学、生物力学测试、组织学和 micro-CT 评估生物相容性、融合状态和降解情况。
Mg-Zn 笼表现出理想的生物相容性和生物力学特性；然而，影像学和组织学评估的融合状态不可接受。经 MAO/Si 涂层改性后，Mg-Zn 笼的降解速率可控，但比预期的要慢。
MAO/Si 涂层 Mg-Zn 合金笼在术后 24 周时表现出过度的降解控制和融合失败。我们得出结论，需要进一步设计研究来改善 Mg 基材料在椎间空间的应用。
