Bauer T W, Geesink R C, Zimmerman R, McMahon J T
Department of Pathology, Cleveland Clinic Foundation, Ohio 44195-5138.
J Bone Joint Surg Am. 1991 Dec;73(10):1439-52.
Plasma-sprayed coating of hydroxyapatite are biocompatible and, because of their osteoconductive properties, may contribute to the early fixation of total joint prostheses. To evaluate this interface, we histologically analyzed five hydroxyapatite-coated femoral stems which, along with the surrounding bone, were retrieved from three humans at autopsy. The five femoral components had been in situ for a mean duration of twelve months (range, almost five to twenty-five months) and had been inserted for osteonecrosis (two), osteoarthrosis (two), and as an uncermented revision for failure of a cemented stem. The three patients had had a good or excellent clinical result and had died of causes unrelated to the joint arthroplasty. A coating of hydroxyapatite was identified on each stem. There was a variable amount of apposition of bone (32 to 78 per cent of available surface per section). The deposition of bone was most prominent on the surface of the prosthesis that was close to the endosteal surface of the bone, especially in areas that are predicted by Wolff's law (anterior and medial aspects of the implant, and at lateral-oblique corners). There were occasional foci of bone-remodeling around the implant, including osteoclast-mediated removal of the coating of hydroxyapatite along with adjacent bone. Occasional particles of ceramic were present within macrophages in the adjacent bone marrow. Other areas showed formation of new bone with a few areas of bone directly against the metal substrate. The over-all histological features suggest mechanically stable implants with bone-remodeling at the surface of the bone-implant interface.
羟基磷灰石等离子喷涂涂层具有生物相容性，并且由于其骨传导特性，可能有助于全关节假体的早期固定。为了评估这种界面，我们对五个羟基磷灰石涂层股骨柄进行了组织学分析，这些股骨柄连同周围的骨头是在尸检时从三名人类身上获取的。这五个股骨部件在位的平均时间为十二个月（范围为近五个月至二十五个月），植入的原因分别是骨坏死（两例）、骨关节炎（两例）以及作为骨水泥柄失败后的非骨水泥翻修。这三名患者临床结果良好或优秀，死于与关节置换术无关的原因。在每个柄上都发现了一层羟基磷灰石涂层。骨附着量各不相同（每切片可用表面的32%至78%）。骨沉积在假体靠近骨内膜表面的区域最为明显，特别是在根据沃尔夫定律预测的区域（植入物的前侧和内侧，以及外侧斜角处）。植入物周围偶尔有骨重塑灶，包括破骨细胞介导的羟基磷灰石涂层连同相邻骨的去除。相邻骨髓中的巨噬细胞内偶尔有陶瓷颗粒。其他区域显示有新骨形成，少数区域有骨直接贴靠金属基质。总体组织学特征表明植入物在机械上是稳定的，并且在骨-植入物界面表面存在骨重塑。
