松动人工髋关节周围组织中聚乙烯磨损颗粒观察

Polyethylene wear in periprosthetic tissue of failed cemented total hip arthroplasties

为探讨聚乙烯磨损及其与人工髋关节松动的关系，作者对６例因人工髋关节臼侧假体松动而行翻修术病例的假体周围软组织、软组织中聚乙烯碎屑及臼杯内表面进行了肉眼、偏光镜及扫描电镜观察，分析了聚乙烯内杯磨损颗粒的产生机制及其在假体周围纤维膜形成、假体松动发生过程中的意义。研究结果显示，假体松动时，在聚乙烯内杯磨损方式中，夹有第三体颗粒（如骨块、骨水泥或金属碎屑）的二个负重面磨擦（三体磨损）占有主要地位。表现为臼杯内表面有明显擦痕，假体周围软组织中可见较多扁平梭形聚乙烯碎屑。大小形态不一的磨损颗粒可被１个或多个多核巨细胞包绕，多核巨细胞不仅数量增多，而且功能活跃，是参与松动形成的重要细胞成份。作者认为，聚乙烯内杯三体磨损所产生的颗粒是诱发多核巨细胞反应、导致髋关节松动的关键因素。

To elucidate the relationship betweem polyethylene wear and loosening of total hip arthroplasty,we observed grossly the periprosthetic tissues, polyethylene wear debris and polyethylene acetabular liners retrieved from 6 failed cemented total hip arthroplasties during revisions by means of polar light miscroscope and scanning electron microscope.The production mechanism of polyethylene wear debris from acetabular liner was analysed together with its role in periprosthetic fibrosis and prosthetic loosening. Results showed the abrasion of two bearing surfaces interposed with third body particles as called three body abrasion was the main model of polyethylene wear. All inner surfaces of the liners appeared clear abrasive scratches and big flat debris were found in most of the retrieved tissues. Histologically, the wear debris of various sizes embraced by 1 or several polynuclear giant cells that were found not only great in number but also active in function. The implication is that three body abrasion is the key factor of high rate wear of the polyethylene liner and that polynuclear giant cell is acting as an important cellular component leading to the prosthetic loosening.