In-Depth Oral Presentations and Oral Communications IN-DEPTH ORAL PRESENTATIONS HIP (FIRST HALF) A new polymer for total hip arthroplasty. First Italian experiences

The success of a total hip arthoplasty is linked to a long survival, and this one is obtained reducing the surfaces wearing. Polyethylene material was introduced by Sir John Charnley in the 60’s and has been until now the cartilage most similar material regarding the Young modulus, despite metal and ceramic ones. It has been also characterized by a good wear, especially nowadays the highly cross-linked polyethylene technology has been developed. In the last years, research has been oriented to already used materials improvement such as metals and metal alloys (steel, titanium, CrCo, tantalum), to study and product dense and bioactive ceramics (alumina), to study and product polymeric and composite materials. The physical properties of some polymers have shown to be very similar to those of the normal cartilage. Considering that the most relevant impairment in an arthritic hip regard the articular cartilage, it’s easy to figure out the importance of regaining the cartilage function in anatomical THA surgery. Years of study and laboratory tests have led to the production of a new acetabulum module made of PCU (polycarbonate urethane), which would play a buffer/plug role, as the normal cartilage of a healthy hip does. The emerging buffer characteristics consist of the mentioned optimum modulus of elasticity which results moreover as a shock absorber, and the optimum microelastodynamic lubrication which reduce the friction coefficient. The buffer is presented as an acetabular cup to be inserted in a metal back (titanium coated CrCoMo) press-fit implanted. It can also be implanted directly in contact with the acetabular bone, previous the thin residual cartilage layer removal, allowing a more anatomical surgery and a bone stock sparing. PCU buffer is intended to be a new way of thinking total hip arthroplasty, nevertheless the acquired experience is actually confined among few Centers and further laboratory tests are going to be concluded. The path has drawn, it has just to be covered!