To assess the efficacy (survivorship) of the Quadra-P Hydroxyapatite coated femoral stem in patients undergoing a primary total hip replacement surgery.

Total Hip Arthroplasty (THA) is a procedure commonly performed in patients who have end-stage hip osteoarthritis. The primary goal of THA is to provide pain relief, reduce disability, improve quality of life and functional status. Despite high implant success rates, up to 15% of patients remain dis-satisfied after surgery. This has been postulated to be due to several factors, including implant loosening, stem fractures and reduced functional movement, which lead to poorer patient outcomes. Recently, a new range of hip replacement devices have been engineered to address some of the shortcomings of existing stems. In particular, the Quadra-P stem has specifically been designed as a straight, triple tapered stem with a rectangular cross-section and manufactured with Ti-6Al-7Nb alloy material to increase osseointegration and reduce wear. The newly designed Quadra-P stem device was recently introduced into the Australian market, however, its clinical performance is yet to be evaluated. Thus, the purpose of this study is to investigate the Quadra-P stem efficacy (survival) at 2, 5 and 10 years post-surgery and ensure that it performs just as well as other commercially available stems. The hypothesis for this investigation is that the 2, 5 and 10 year percent revision rate (need to re-implant) is not inferior (comparable) to the average performance of all other cementless femoral stems currently in use in the Australian Market.