University of Nottingham, Academic Orthopaedics, Trauma and Sports Medicine, Queen's Medical Centre, Nottingham, NG7 2UH,
Eur Cell Mater. 2014 Jun 8;27:332-49. doi: 10.22203/ecm.v027a24.
Open fractures are at risk of serious infection and, if infected, require several surgical interventions and courses of systemic antibiotics. We investigated a new injectable formulation that simultaneously hardens in vivo to form a porous scaffold for bone repair and delivers antibiotics at high concentrations to the local site of infection. Duration of antimicrobial activity against Staphylococcus aureus was determined using the serial plate transfer test. Ultimate compressive strength and porosity of the material was measured with and without antibiotics. The material was evaluated in vivo in an ovine medial femoral condyle defect model contaminated with S. aureus. Sheep were sacrificed at either 2 or 13 weeks and the defect and surrounding bone assessed using micro-computed tomography and histology. Antimicrobial activity in vitro persisted for 19-21 days. Sheep with antibiotic-free material and bacteria became infected, while those with antibiotic-containing material and bacteria did not. Similarly, new bone growth was seen in uninoculated animals with plain polymer, and in those with antibiotic polymer with bacteria, but not in sheep with plain polymer and bacteria. The antibiotic-impregnated scaffolds were effective in preventing S. aureus infections whilst supporting bone growth and repair. If translated into clinical practice, this approach might reduce the need for systemic antibiotics.
开放性骨折有发生严重感染的风险，如果发生感染，则需要多次手术干预和全身使用抗生素。我们研究了一种新的可注射制剂，该制剂在体内可同时变硬，形成用于骨修复的多孔支架，并将抗生素以高浓度递送到感染的局部部位。采用连续平板转移试验测定对金黄色葡萄球菌的抗菌活性持续时间。测量了有无抗生素时材料的最终抗压强度和孔隙率。该材料在感染金黄色葡萄球菌的绵羊股骨内侧髁缺损模型中进行了体内评估。绵羊在 2 或 13 周时被处死，使用微计算机断层扫描和组织学评估缺损和周围骨骼。体外抗菌活性持续 19-21 天。无抗生素材料和细菌的绵羊发生感染，而含抗生素材料和细菌的绵羊则没有。同样，未接种的动物的普通聚合物以及有细菌的含抗生素聚合物中可见新骨生长，但无细菌的普通聚合物中则没有。抗生素浸渍支架可有效预防金黄色葡萄球菌感染，同时支持骨生长和修复。如果转化为临床实践，这种方法可能减少对全身抗生素的需求。
