La Fissazione.

The aim of our study is to review the most important concepts in the prosthesis technique fixation. The elements for a successful prosthesis implantation are due to the prosthesis design, the pattern of fixation, the articular tribology, and the surgical accuracy. Also other factors like osteonecrosis, toxicity of the implanted materials, the early stability and the time and the bearing of the implanted prosthesis, affect deeply the implant-bone surface and therefore the quality of fixation. The cemented fixation is based on the acrylic cement and is commonly considered the easier, the most effective and the less expensive fixation technique. The uncemented fixation allows a lower surgical time due to the implantation technique. This technique more difficult than the cemented fixation, is based on the osteointegration. The hybrid fixation presents components each with different fixation techniques. On the contrary, the polyurethane prosthesis does not use a real fixation, but fits on the articular surfaces in which they are inserted. However the elements that should always lead to treatment choice are the specific surgical aptitude and knowledge of the literature results based on the scientific evidence.