A purely Anatomic femoral implant The concept OPAL was designed more than 15 years ago to provide a solution to the latest requirements of the patients and their surgeons in term of comfort, reduction of the complications, reproducibility of the articular physiology, and longevity of the arthroplasty. The concept of the anatomical implant is meant to optimize the metaphyso-epiphysar contact area and to reduce proportionally the peri-prosthtic osseous remodelling. The body of the implant is more naturally stable against subsidence and rotation, and its "optimal" indexation in the femoral epiphysis positions automatically the prosthetic neck in a natural plan of retroversion. OPALE is only intended for use without cement. The implant is made in titanium alloy and is proximally coated with porous titanium and hydroxyapatite.