Willert H G, Bertram H, Buchhorn G H
Department of Orthopaedics, University of Göttingen, Federal Republic of Germany.
Clin Orthop Relat Res. 1990 Sep(258):95-107.
Massive localized osteolysis around artificial joints has been seen more frequently in the past few years. It is still not generally accepted that ultra-high molecular weight polyethylene (UHMWPE) wear particles can induce massive bone resorption, even distant from the joint. This article describes a series of eight soft-top prostheses with large UHMWPE ball heads that contributed to the erosion of surrounding bone. Roentgenographically, all of the cases showed a marked loss of proximal cortical bone, more or less combined with osteolysis, which was distal to the femoral shaft and deep into the acetabulum. In two cases, remodeling and resorption transformed the bone into a tumorlike appearance. Tissue samples from areas of osteolysis as well as from the joint capsule were taken at revision surgery, processed for histology, examined microscopically, and evaluated semiquantitatively. The retrieved devices were also carefully inspected. Large amounts of UHMWPE wear debris were found not only in the joint capsule but also in layers of granulomatous tissue from the acetabulum and femur, whereas metal particles and fragmented polymethylmethacrylate were either completely absent or occurred only in very small amounts. The results of this study demonstrate that UHMWPE wear products alone can cause massive osteolysis by triggering foreign-body granuloma formation at the bone-cement interface; the bone cement may remain fixed in areas beyond the osteolytic transformation.
在过去几年中，人工关节周围出现大量局限性骨质溶解的情况更为常见。超高分子量聚乙烯（UHMWPE）磨损颗粒可引发大量骨吸收，甚至在远离关节的部位，这一观点仍未被普遍接受。本文描述了一系列八个带有大型UHMWPE球头的软顶假体，这些假体导致了周围骨质的侵蚀。在X线片上，所有病例均显示近端皮质骨明显缺失，或多或少合并有骨质溶解，骨质溶解位于股骨干远端并深入髋臼。在两例病例中，重塑和吸收使骨骼呈现出肿瘤样外观。在翻修手术时，从骨质溶解区域以及关节囊获取组织样本，进行组织学处理，显微镜检查并进行半定量评估。对取出的假体也进行了仔细检查。不仅在关节囊中，而且在髋臼和股骨的肉芽肿组织层中都发现了大量的UHMWPE磨损碎片，而金属颗粒和破碎的聚甲基丙烯酸甲酯要么完全不存在，要么仅以极少量出现。本研究结果表明，仅UHMWPE磨损产物就可通过在骨水泥界面引发异物肉芽肿形成而导致大量骨质溶解；骨水泥可能在骨质溶解转化区域之外保持固定。
