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 .
Migration of the uncemented Harris-Galante acetabular cup: results of the einbildroentgenanalyse (EBRA) method.
Seventy primary total hip arthroplasties using the Harris-Galante acetabular cup ( Zimmer , Warsaw , IN ) were prospect ively examined . Over the entire period of 65.4+/-7.8 months ,  radiologic migration analysis  was performed using the  Einbildroentgenanalyse  ( EBRA ) method at an accuracy of 1 mm . Although there was clinical ly no suspicion of prosthetic loosening in any case , in 8 implants ( 11.4 % ) migration of more than 1 mm was observed . Cranial migration occurred in 3 cases ( 1.1 , 1.3 and 1.6 mm ) , medial migration in 3 cases ( 1.1 , 1.1 , and 2.9 mm ) , and lateral migration in 2 cases ( 1.1 and 1.1 mm ) . In the other 62 cases , however , no migration was traceable . Compared with measurements of other implant systems by means of the EBRA method published recently by other groups , the migration rate of the Harris-Galante cup was without exception lower and provided excellent midterm implant stability
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 .