家兔股骨植入可降解型镁合金加压螺钉的生物效应与抗菌性能研究

Observation on Biological Effects and Antibacterial Properties of Degradable Magnesium Alloycompression Screws Implanted into Rabbit Femur

目的评价一种新型可降解镁合金螺钉作为植入物在家兔股骨干上的生物安全性、降解性与抗菌性。方法选取成年家兔20只,随机分为对照组与实验组,各10只。实验组行麻醉后在股骨骨干钻孔后向骨髓腔内注射入金黄色葡萄球菌菌液并加压植入镁合金螺钉固定,对照组与上述手术处理相同,但不植入镁合金螺钉。60 d后对实验家兔行影像学、组织切片、金黄色葡萄球菌检测及离体股骨形态观察。结果镁合金螺钉降解后的股骨形态:60 d后螺钉完全降解消失,原植入部位形成膨大的骨痂,周围组织无坏死无炎症;影像学检测:术后30 d时可观察到螺钉开始降解且固定良好,术后60 d螺钉已完全消失,周围骨组织无坏死样症状;骨组织切片检测:染色后观察可见植入部位成骨细胞增加,骨细胞增生呈无序排列;金黄色葡萄球菌检测:实验组金黄色葡萄球菌阴性率90.00%,对照组金黄色葡萄球菌阴性率20.00%。结论新型可降解镁合金螺钉作为骨科固定物,在生物降解吸收方面与抗菌方面展现出优良的效果,其具有生物安全性高、降解完全、促进骨生长、避免二次手术等优良特性。

Objective To evaluate the biosafety,degradability and antimicrobial activity of a new degradable magnesium alloy screw as an implant on the femoral shaft of rabbits.Methods Totally 20 adult rabbits were randomly divided into the experimental group and the control group with 10 rabbits each.After anesthesia,the experimental group was injected with Staphylococcus aureus bacterial solution into the bone marrow cavity after drilling the shaft of the femur,and magnesium alloy screws were inserted into the bone marrow cavity under pressure for fixation.The control group underwent the same surgical treatment as above,but no magnesium alloy screws were implanted.Sixty days later,imaging,histological section,Staphylococcus aureus detection and the morphology of femur in vitro were observed.Results The morphology of femur after magnesium alloy screw degradation:60 d later,the screw completely degraded and disappeared,and the original implant site formed an enlarged callus without necrosis and inflammation in the surrounding tissues.Imaging detection:30 d after the operation,the screw began to degrade and was well fixed;60 d after the operation,the screw completely disappeared,and the surrounding bone tissue had no necrosis symptoms.Detection of bone tissue sections:the bone cells were increased and the proliferation of bone cells was disordered after staining.Staphylococcus aureus detection:the experimental group Staphylococcus aureus negative rate of 90.00%,the control group Staphylococcus aureus negative rate of 20.00%.Conclusion The new biodegradable magnesium alloy screws as orthopedic fixation have shown excellent effects in biodegradable absorption and antibacterial,with high biological safety,complete degradation,promoting bone growth,avoiding secondary surgery and other excellent characteristics.