Investigations of microstructure of porous coated orthopaedic implants in the aspect of the structural-adaptive compatibility of bone-porous implant interface. Part 1, Critical view on bone-implant fixation problem

Abstract

The biomechanical construction of orthopaedic implants, e.g. construction of an artificial hip joint, is characterized by a set of material, geometrical and dynamic properties, designed to fulfil required assumptions. From the biomechanical point of view the problem of structuralbiomechanical compatibility between impalnt and bone is a key-question in respect of the role performed in the skeleton. At first in the matter, the problem of structural-adaptive compatibility of orthopaedic implants porous coatings with bone tissue (natural porous biomaterial) should be stated. This problem deals with osteoinductive properties of biomaterial. The osteoinductive properties of biomaterial are determined, among others, by the poroaccessibility of porous coating for adaptive ingrowth of bone tissue into its pore space which is influenced by mechanical load history. The aim of bone ingrowth into pore space of a coating is to achieve the proper and permanent fixation of the implant in its bony surroundings. This part of the paper presents insight view into the problem of bone-implant fixation, and a critical review of the traditional approach to investigations on the cementless implant fixation conditioned by the bone tissue ingrowth, which were carried out on the basis of one-phase biomechanical model of bone.