Hardy D C, Frayssinet P, Krallis P, Descamps P Y, Fabeck L, Delplancke J L, Delince P E
Department of Orthopedics and Traumatology, CHU Saint-Pierre, Brussels, Belgium.
Acta Orthop Belg. 1999 Mar;65(1):72-82.
A fully hydroxyapatite-coated femoral implant was retrieved during autopsy. This component, provided with a bipolar femoral head, had been inserted for a displaced fracture of the femoral neck 52 months before. Osseointegration of the implant was evident, without any formation of fibrous tissue :39.9% of the perimeter of the prosthesis at the level of its proximal third was interfaced with bone (62.8% at the mid-third and 65.2% at the distal third). Remodeling of bone had ensued. Deposition of bone was most prominent in the calcar zone, along the medial and lateral aspects and around the tip. Proximally, cortical porosity was found to be increased by 73%, whereas medullary bone porosity was increased by a factor of 2. Cell-mediated resorption of the coating was systematically present in these bone remodeling areas. The average thickness of the coating was respectively 10.8, 50.2 and 151.2 microns in the proximal, mid- and distal thirds of the implant. Formation of new bone was often coupled with resorption. No debris from the coating was found in the joint tissues or in the articulating surface of the polyethylene insert. These overall histopathological features support mechanical stability of the implant and active remodelling of bone along with focal removal of HA coating associated with osteoclastic activity. No side effects from coating degradation could be demonstrated.
在尸检过程中取出了一个完全羟基磷灰石涂层的股骨植入物。该部件配有双极股骨头，于52个月前因股骨颈移位骨折而植入。植入物的骨整合明显，没有任何纤维组织形成：假体近端三分之一处39.9%的周长与骨相接（中部三分之一处为62.8%，远端三分之一处为65.2%）。随后发生了骨重塑。在骨小梁区、内侧和外侧以及尖端周围，骨沉积最为明显。在近端，皮质骨孔隙率增加了73%，而髓质骨孔隙率增加了一倍。在这些骨重塑区域中，涂层的细胞介导吸收普遍存在。在植入物的近端、中部和远端三分之一处，涂层的平均厚度分别为10.8、50.2和151.2微米。新骨形成常常与吸收同时发生。在关节组织或聚乙烯内衬的关节表面未发现涂层碎片。这些总体组织病理学特征支持植入物的机械稳定性以及骨的积极重塑，同时伴有与破骨细胞活性相关的HA涂层局部去除。未发现涂层降解的副作用。
