Yñiguez Francisco Morales, Grimes Janet A, Hodgson Michelle M, Trenta Margaret, Liu Chin-Chi, Riggs Laura M
Am J Vet Res. 2024 Jul 31;85(10). doi: 10.2460/ajvr.24.06.0170. Print 2024 Oct 1.
The objective of this study was to determine the effects of repeated steam sterilization cycles on the biomechanical properties of surgical screws.
42 3.5-mm and 42 2.0-mm self-tapping, cortical screws were divided into 3 groups per size and underwent autoclave sterilization for 1 (G1), 50 (G50), or 100 (G100) cycles and testing from August 2018 through June 2021. Sixty screws were then inserted into canine cadaver femurs, and biomechanical properties were measured, including peak insertional torque, torque to failure, and pullout strength, each normalized to cortical thickness. Scanning electron micrographs were taken from 24 screws, and images were blindly analyzed by 5 trained examiners.
The mean normalized insertion torque for 3.5-mm screws was significantly different between G1 and both G50 and G100. The mean normalized torque to failure for 3.5-mm screws was significantly different between G1 and both G50 and G100. Axial pullout testing was found to be significantly different for 2.0-mm screws between G1 and G100. Scanning electron micrographs surface scoring identified a significant difference in 3.5-mm screws at the screw tip.
The results indicate that biomechanical changes occur with repeated steam sterilizations. Specifically, peak insertional torque and torque to failure are decreased with increased sterilizations for 3.5-mm screws, whereas 2.0-mm screws were altered in pullout testing after 100 sterilizations. It is suspected that numerous sterilizations negatively alter the physical-mechanical properties of certain screw sizes.
The biomechanical properties of the bone-implant interface could negatively be affected by multiple steam sterilizations during clinical setting.
本研究的目的是确定重复蒸汽灭菌循环对外科螺钉生物力学性能的影响。
将42枚3.5毫米和42枚2.0毫米的自攻皮质螺钉按尺寸分为3组，于2018年8月至2021年6月期间进行高压蒸汽灭菌1次（G1组）、50次（G50组）或100次（G100组），然后进行测试。随后将60枚螺钉植入犬类尸体股骨中，测量生物力学性能，包括峰值插入扭矩、破坏扭矩和拔出强度，每项均根据皮质厚度进行标准化。对24枚螺钉拍摄扫描电子显微镜照片，并由5名经过培训的检查人员进行盲法分析。
3.5毫米螺钉的平均标准化插入扭矩在G1组与G50组和G100组之间存在显著差异。3.5毫米螺钉的平均标准化破坏扭矩在G1组与G50组和G100组之间存在显著差异。发现2.0毫米螺钉的轴向拔出测试在G1组和G100组之间存在显著差异。扫描电子显微镜照片表面评分显示，3.5毫米螺钉在螺钉尖端存在显著差异。
结果表明，重复蒸汽灭菌会导致生物力学变化。具体而言，3.5毫米螺钉的峰值插入扭矩和破坏扭矩随着灭菌次数的增加而降低，而2.0毫米螺钉在100次灭菌后的拔出测试中发生了变化。怀疑多次灭菌会对某些尺寸螺钉的物理力学性能产生负面影响。
在临床环境中，多次蒸汽灭菌可能会对骨植入物界面的生物力学性能产生负面影响。
