Department of Trauma Surgery, University Hospital of Giessen-Marburg GmbH, and Laboratory of Experimental Trauma Surgery, Institute of Medical Computer Sciences, Justus-Liebig-University Giessen, Campus Giessen, 35385 Giessen, Germany.
Acta Biomater. 2011 Mar;7(3):1274-80. doi: 10.1016/j.actbio.2010.11.012. Epub 2010 Dec 1.
Antimicrobial coatings are of interest as a means to improve infection prophylaxis in cementless joint arthroplasty. However, those coatings must not interfere with the essential bony integration of the implants. Gentamicin-hydroxyapatite (gentamicin-HA) and gentamicin-RGD (arginine-glycine-aspartate)-HA coatings have recently been shown to significantly reduce infection rates in a rabbit infection prophylaxis model. The purpose of the current study was to investigate the in vitro elution kinetics and in vivo effects of gentamicin-HA and gentamicin-RGD-HA coatings on new bone formation, implant integration and biocompatibility in a rabbit model. In vitro elution testing showed that 95% and 99% of the gentamicin was released after 12 and 24 h, respectively. The in vivo study comprised 45 rabbits in total, with six animals for each of the gentamicin-HA, gentamicin-RGD-HA group and control pure HA coating groups for the 4 week time period, and nine animals for each of the three groups for the 12 week observation period. A 2.0 mm steel K-wire with one of the coatings under test was placed in the intramedullary canal of the tibia. After 4 and 12 weeks the tibiae were harvested and three different areas (proximal metaphysis, shaft area, distal metaphysis) were assessed by quantitative and qualitative histology for new bone formation, direct implant-bone contact and the formation of multinucleated giant cells. The results exhibited high standard deviations in all subgroups. There was a trend towards better bone formation and better direct implant contact in the pure HA coating group compared with both gentamicin coatings after 4 and 12 weeks, which was, however, not statistically significant. The number of multinucleated giant cells did not differ significantly between the three groups at both time points. In summary, both gentamicin coatings with 99% release of gentamicin within 24 h revealed good biocompatibility and bony integration, which was not statistically significant different compared with pure HA coating. Limitations of the study are the high standard deviation of the results and the limited number of animals per time point.
抗菌涂层作为一种提高非骨水泥关节置换术感染预防的手段受到关注。然而，这些涂层不能干扰植入物的基本骨整合。最近的研究表明，庆大霉素-羟基磷灰石（gentamicin-HA）和 gentamicin-RGD（精氨酸-甘氨酸-天冬氨酸）-HA 涂层可显著降低兔感染预防模型中的感染率。本研究的目的是研究庆大霉素-HA 和 gentamicin-RGD-HA 涂层在兔模型中新骨形成、植入物整合和生物相容性的体外洗脱动力学和体内效应。体外洗脱试验表明，分别在 12 和 24 h 后释放了 95%和 99%的庆大霉素。体内研究共包括 45 只兔子，每组 6 只，庆大霉素-HA、gentamicin-RGD-HA 组和对照纯 HA 涂层组各 4 周，3 组各 9 只观察 12 周。在胫骨骨髓腔内放置一根带有测试涂层之一的 2.0mm 钢 K 线。4 和 12 周后，取出胫骨，通过定量和定性组织学评估新骨形成、直接植入物-骨接触和多核巨细胞形成的三个不同区域（近干骺端、骨干区、远干骺端）。所有亚组的结果均显示出较高的标准偏差。与两种庆大霉素涂层相比，纯 HA 涂层在 4 周和 12 周时均显示出更好的骨形成和更好的直接植入物接触趋势，但无统计学意义。在两个时间点，三组之间多核巨细胞的数量没有显著差异。总之，两种 gentamicin 涂层在 24 h 内释放 99%的 gentamicin 显示出良好的生物相容性和骨整合性，与纯 HA 涂层相比无统计学差异。本研究的局限性是结果的标准差较高，每个时间点的动物数量有限。
