Chen Gaoyang, Liu Bo, Liu He, Zhang Hanyang, Yang Kerong, Wang Qingyu, Ding Jianxun, Chang Fei
Department of orthopaedic surgery, 2nd Hospital of Jilin University, No. 218, Ziqiang street, Nanguan District, Changchun 130041, China.
Department of orthopaedic surgery, the First Hospital of Jilin University, Changchun, China.
Orthop Traumatol Surg Res. 2018 Dec;104(8):1271-1275. doi: 10.1016/j.otsr.2018.07.007. Epub 2018 Aug 11.
Antibiotics impregnated calcium phosphate cement (CPC) has emerged as a local treatment of osteomyelitis. However, there is no study investigating the optimal concentrations of vancomycin (VCM) included in CPC to obtain prolonged drug release (≥8 weeks) and also with enough compressive strength (>the normal cancellous bone, 11MPa) for osteomyelitis therapy. Therefore, we bring forward two questions: 1) Was antibiotic activity of the eluates correlated to the load of antibiotics within the cement? 2) Were the mechanical properties of CPC affected by VCM-loading?
There was an optimal concentrations of vancomycin (VCM) loaded in CPC which could provide sufficient effective antibacterial time (≥8 weeks) and enough compressive strength (>11MPa).
CPC specimens were obtained by incorporating different doses (weigh ratios of 0%, 5%, 10%, 15%, 20%, 25 and 30%) of injectable VCM into CPC. The antibacterial effect of released VCM solution against Staphylococcus aureus was assessed by inhibition ring assays. The physicochemical properties such as compressive strengths were characterized and compared among these specimens.
Drug release profiles showed only 5 and 10% VCM-loaded CPC displayed a long enough drug release time (at least 8 weeks) and maintained the eluate concentrations (>4μg/mL) with effective antibacterial ability. The concentration of VCM in 10% group at 8th week was twice higher than 5% group. Compressive strength test showed that the proportional increase of VCM/CPC ratios resulted in a significant decrease of compressive strength (r=-0.906, p<0.001).
10% VCM-loaded CPC offered the optimal physicochemical properties and drug releasing profile and appears as the most suitable concentration for clinical use.
III.
抗生素浸渍磷酸钙骨水泥（CPC）已成为治疗骨髓炎的一种局部治疗方法。然而，尚无研究调查CPC中万古霉素（VCM）的最佳浓度，以实现药物的长期释放（≥8周），同时具有足够的抗压强度（>正常松质骨，11MPa）用于骨髓炎治疗。因此，我们提出两个问题：1）洗脱液的抗生素活性与骨水泥中抗生素的负载量相关吗？2）VCM负载会影响CPC的力学性能吗？
CPC中负载的万古霉素（VCM）存在最佳浓度，可提供足够长的有效抗菌时间（≥8周）和足够的抗压强度（>11MPa）。
通过将不同剂量（重量比为0%、5%、10%、15%、20%、25%和30%）的可注射VCM掺入CPC中获得CPC标本。通过抑菌圈试验评估释放的VCM溶液对金黄色葡萄球菌的抗菌效果。对这些标本的抗压强度等物理化学性质进行表征和比较。
药物释放曲线显示，仅5%和10% VCM负载的CPC显示出足够长的药物释放时间（至少8周），并保持洗脱液浓度（>4μg/mL）且具有有效的抗菌能力。第8周时，10%组的VCM浓度是5%组的两倍。抗压强度测试表明，VCM/CPC比例的成比例增加导致抗压强度显著降低（r=-0.906，p<0.001）。
10% VCM负载的CPC具有最佳的物理化学性质和药物释放曲线，似乎是最适合临床使用的浓度。
III级。
