Bone-Prosthesis Implant Relation in Total Cementless Hip Arthroprosthesis

Abstract

The best relation between bone and prosthetic implant occurs when an adequate bone surface preparation and a correct implant placing ensure wide interface contact, with homogeneous load distribution (primary stability). This is necessary premise to achieve osteointegration (secondary stability) which is conditioned by factors connected with the implant (materials, surface work, lining) and with the hosting bone (pathological onset, sex, age). The evolution of bone-implant relation leads to the formation of fibrous or osseous interface; the stimulus which act on the interface (in relation with primary stability, distance between surfaces, bony heritage, etc…) infact determine a fibroblastic or osteoblastic evolution of mesenchymal elements colonizing the interface during the initial phases. In successive phases the prevailing apposition (hyperthropy) or resorption (focal or diffuse atrophy) processes is equally conditioned by mechanical factors (the position and dimension of the implant).