The Charnley prosthesis had by far the best and most comprehensive evidence base with better than 90 % implant survival after about 10 years .
Some uncemented stems have shown promising medium-term outcome , but no combination of uncemented cup and stem fulfilled the benchmark criterion of > or = 90 % implant survival at 10 years , which we propose as a minimum requirement for unrestricted clinical use for prostheses used in primary THR .
We have conducted a systematic review of the scientific literature concerning outcome and clinical effectiveness of  prostheses used for primary total hip replacement ( THR ) in Norway .
Cementless Acetabular Replacement in the Young: A 5- to 10-Year Prospective Study
This article presents a prospect i ve clinical and radiologic review of 55 total hip replacements in 50 patients in which the cementless Harris-Galante porous-coated acetabular component was used . All patients were 50 years of age or younger . The cups were inserted by 15 different surgeons . The minimum followup was 5 years , with a mean of 7 years . No acetabular component has been revised for loosening , and none have migrated . Three ( 5.5 % ) cups have progressive bone-component radiolucent lines , two ( 3.6 % ) of which are complete . Six ( 10.9 % ) acetabular liners have been replaced for excessive polyethylene wear , and an additional four ( 7.3 % ) show sufficient wear to produce obvious radiographic eccentricity of the femoral head . All of the revised liners had 32-mm femoral heads and an initial polyethylene thickness of less than 6 mm . Although the results reflect excellent fixation of this component in the medium term , the incidence of exchange of the polyethylene liner for excessive wear is unacceptably high . The reduction in polyethylene thickness associated with the use of a metal-backed component and a 32-mm articulation was one of the factors contributing to the accelerated wear patterns seen in this series
The Charnley prosthesis had by far the best and most comprehensive evidence base with better than 90 % implant survival after about 10 years .
Some uncemented stems have shown promising medium-term outcome , but no combination of uncemented cup and stem fulfilled the benchmark criterion of > or = 90 % implant survival at 10 years , which we propose as a minimum requirement for unrestricted clinical use for prostheses used in primary THR .
We have conducted a systematic review of the scientific literature concerning outcome and clinical effectiveness of  prostheses used for primary total hip replacement ( THR ) in Norway .