Jakobsen Stig S, Baas Jorgen, Jakobsen Thomas, Soballe Kjeld
Department of Orthopaedics, Aarhus University Hospital, Aarhus, Denmark.
Hip Int. 2010 Apr-Jun;20(2):171-8. doi: 10.1177/112070001002000207.
Induction of bone ingrowth by topographical changes to implant surfaces is an attractive concept. Topographical modifications achieved by acid etching are potentially applicable to complex 3D surfaces. Using clinically relevant implant models, we explored the effect of wet etching porous bead-coated CoCrMo. The study was designed as two paired animal experiments with 10 dogs. Each dog received four implants; one in each medial femoral condyle (loaded 0.75-mm-gap model) and one in each proximal tibia (press-fit). The implants were observed for 6 weeks and were evaluated by biomechanical pushout tests and histomorphometry. We found that wet etching porous bead-coated CoCrMo implants failed to improve implant performance. Moreover, a tendency towards increased fibrous tissue formation, decreased new bone formation, and decreased mechanical fixation was observed. Surface topography on implants is able to stimulate bone-forming cells, but the clinical performance of an implant surface perhaps relies more on 3D geometrical structure and biocompatibility. Caution should be exercised regarding the results of wet etching of porous bead-coated CoCrMo and there is a need for more preclinical trials.
通过改变植入物表面形貌诱导骨长入是一个颇具吸引力的概念。通过酸蚀实现的形貌改变可能适用于复杂的三维表面。利用临床相关的植入物模型，我们探究了湿法蚀刻多孔珠涂层钴铬钼合金的效果。该研究设计为两项配对动物实验，共有10只狗参与。每只狗植入四枚植入物；每侧股骨内侧髁各一枚（采用0.75毫米间隙加载模型），每侧胫骨近端各一枚（压配式）。对植入物进行6周观察，并通过生物力学推出试验和组织形态计量学进行评估。我们发现，湿法蚀刻多孔珠涂层钴铬钼合金植入物未能改善植入物性能。此外，还观察到纤维组织形成增加、新骨形成减少以及机械固定力下降的趋势。植入物表面形貌能够刺激成骨细胞，但植入物表面的临床性能可能更多地依赖于三维几何结构和生物相容性。对于多孔珠涂层钴铬钼合金湿法蚀刻的结果应谨慎对待，并且需要进行更多的临床前试验。
