Smith T J, Galm A, Chatterjee S, Wells R, Pedersen S, Parizi A Meimandi, Goodship A E, Blunn G W
Centre for Biomedical Engineering, Institute of Orthopaedics and Musculoskeletal Science, University College London, Stanmore, Middlesex, HA7 4LP, United Kingdom.
J Orthop Res. 2006 Jul;24(7):1377-83. doi: 10.1002/jor.20170.
To evaluate soft tissue reactions and biofilm formation on percutaneous external fixator screws coated with diamond-like carbon (DLC) and hydroxyapatite (HA) coatings on stainless-steel (SS) pins in an ovine loaded osteotomy model, an Orthofix external fixator was used to stabilize a 3-mm tibial midshaft osteotomy with six tapered pins inserted into the right tibia of 32 skeletally mature Friesland ewes. Animals were divided into four groups; SS, fully coated HA, DLC, and HA-coated threads. At 10 weeks, specimens were harvested and the pins were removed en bloc to examine the interfaces between the surface coatings and the tissues. Fully coated HA pins had a significantly higher percentage of dermal contact with the pin surface than HA-coated threads (p=0.028). The presence of a biofilm was evident on all pin surfaces except DLC-coated pins. Significantly greater numbers of bacteria were present on fully coated HA and plain stainless-steel pins compared with DLC. The surface of DLC-coated pins had a significantly lower number of bacterial colonies compared to SS (p=0.028) and fully coated HA pins (p=0.005). Fully coated HA pins have greater dermal attachment to the pin surface than the other pin coatings investigated. DLC-coated pins have the potential to prevent biofilm formation and bacterial colonization that may reduce infection and consequent pin loosening. An external fixator pin that is partially coated with HA to encourage bone and soft tissue integration and with DLC to reduce biofilm formation is advocated.
在羊负载截骨模型中，为评估涂有类金刚石碳（DLC）和羟基磷灰石（HA）涂层的不锈钢（SS）针上经皮外固定螺钉的软组织反应和生物膜形成情况，使用Orthofix外固定器稳定3毫米胫骨中段截骨，将六根锥形针插入32只骨骼成熟的弗里斯兰母羊的右胫骨。动物被分为四组：SS、全涂层HA、DLC和HA涂层螺纹。在10周时，采集标本并将针整体取出，以检查表面涂层与组织之间的界面。全涂层HA针与针表面的皮肤接触百分比显著高于HA涂层螺纹（p = 0.028）。除DLC涂层针外，所有针表面均明显存在生物膜。与DLC相比，全涂层HA针和普通不锈钢针上的细菌数量明显更多。与SS（p = 0.028）和全涂层HA针（p = 0.005）相比，DLC涂层针表面的细菌菌落数量显著更低。全涂层HA针与其他研究的针涂层相比，对针表面的皮肤附着更强。DLC涂层针有潜力预防生物膜形成和细菌定植，这可能减少感染及随之而来的针松动。提倡一种部分涂有HA以促进骨和软组织整合且涂有DLC以减少生物膜形成的外固定针。
