The relationship between bone resorbing factors and loosening after hip prosthetic replacement.

在种植体周围经常观察到放射区逐渐扩大，导致假体松动。本研究的目的是阐明反射区形成的机理。辐射透光区可分为线性型和侵蚀型，并对两组的组织学和生化结果进行了比较。界面膜是在手术翻修骨水泥THA或无骨水泥双极假体内置换术时从患者处获得的。髋关节置换术后，植入物周围的骨吸收有两条不同的途径。第一种途径可能是通过来自异体肉芽肿的化学介质和酶促进骨吸收。第二种可能的途径是由于生物力学不稳定的植入物引起的机械应力导致骨坏死。组织学上，骨溶解型的界面含有更多的碎片、巨噬细胞和巨细胞，比线性型多。部分巨噬细胞、巨细胞和滑膜样细胞抗白细胞介素-6抗体和TRAP染色阳性。溶骨型匀浆中IL-6和IL-8水平明显高于lincar型匀浆。用胶原酶解离界面膜，在牙本质切片上培养2小时至1周，研究巨噬细胞和巨细胞是否能自行吸收骨。大部分细胞染色时均采用巨噬细胞标记物NSE染色，2小时后未进行TRAP染色。1周时，TRAP阳性的单核和多核巨细胞增多，但未见吸收坑和f -肌动蛋白环形成。根据这些发现，在骨溶解过程中巨噬细胞产生IL-6，激活宿主骨中的破骨细胞，而IL-8除了吞噬碎片外，还可能与异物肉芽肿的形成有关。虽然部分巨噬细胞被TRAP染色，但巨噬细胞可能难以分化为具有骨吸收能力的破骨细胞样细胞。少

The progressive enlargement of the radiolucent area has often been observed around the implant, leading to loosening of the prosthesis. The purpose of this study is to elucidate the mechanism of rediolucent area formation. The radiolucent areas could be classified into the linear type and the erosive type, and these two groups were compared as to the histological and biochemical results. The interface membranes were obtained from patients at the time of surgery for revision of either cemented THA or cementless bipolar endprosthetic replacement.The bone resorption around the implant after hip prosthetic replacement occurs in two different pathways. The first pathway may be cnhanccd bone resorption by chemical mediators and enzyme derived from foreigne body granulomas. The second possible pathway would be the bone necrosis by mechanical stresses due to biomechanically unstable implant.Histologically, the interfaces of the osteolysis type contained more debris, macrophages, and giant cell … More s than the linear type. Some macrophages, giant cells and synovial like cells were positively stained with anti-interleukin-6 antibody and TRAP.The levels of IL-6 and IL-8 in the homogenates from osteolysis type were significantly higher than those from the lincar type. The interface membrancs were dissociated by collagenase, and cultured on dentine slices from 2 hours to 1 week in order to study whether the macrophages and giant cells can resorb bone by themselves. Most of coltured cells were stained with NSE of a marker of macrophage, and weren't stained with TRAP at 2 hours. TRAP positive mononucleated and polynucleated giant cells were increased at 1 week, but both of resorption pit and F-actin ring formation weren't observed.According to these findings, macrophages in osteolysis produce IL-6 which activated osteoclast in host bone, and IL-8 which might relate to the formation of foreign body granuloma in addition to the phagocyte of debris. Although some macrophages are stained with TRAP, it might be difficult for macrophages to differentiate to the osteoclast like cells which were capable of bone resorption. Less