Conclusions Current published evidence does not support survivorship differences among commonly used bearing surfaces in patients younger than age 65 years undergoing THA at short- to mid-term followup .
Background  Total hip arthroplasty ( THA )  is increasingly being performed in patients with long life expectancies and active lifestyles .
Newer implant bearing surfaces , with superior wear characteristics , often are used in this cohort with the goal of improving longevity of the prosthesis , but comparisons across the numerous available bearing surfaces are limited , so the surgeon and patient may have difficulty deciding which implants to use .
Questions / purpose sThe purpose of this study was to answer the following question : Is there a short- to mid-term survivorship difference between common THA bearings used in patients younger than age 65 years ?
New polyethylenes in total hip replacement: a prospective, comparative clinical study of two types of liner.
Ultra-high-molecular-weight polyethylene sterilised in the absence of air and highly cross-linked polyethylene have been used to avoid osteolysis and loosening in total hip replacement . Our prospect i ve r and omised study has assessed the results using two different polyethylenes associated with the same prosthetic design . We assessed 45 Allofit acetabular components with a Sulene-polyethylene liner of conventional polyethylene gamma sterilised with nitrogen and 45 Allofit acetabular components with a Durasul-polyethylene liner sterilised in ethylene oxide , both matched with an Alloclassic stem  with a 28 mm modular femoral head . The prostheses were implanted between May 1999 and December 2001 . The mean follow-up was for 66.3 months ( 60 to 92 ) . The linear penetration of the femoral head was estimated at 6 weeks , at 6 and 12 months and annually thereafter from st and ardised digitised radiographs using image- analysis software . There was no loosening of any prosthetic component . There were no radiolucent lines or osteolysis . The mean rate of penetration calculated from regression analysis during the first five years was 38 microm/year ( SD 2 ) for the Sulene group and 6 microm/year ( SD 1 ) for the Durasul group ( p = 0.00002 ) . The rate of penetration of the Durasul group was 15.7 % of that of the Sulene group
Conclusions Current published evidence does not support survivorship differences among commonly used bearing surfaces in patients younger than age 65 years undergoing THA at short- to mid-term followup .
Background  Total hip arthroplasty ( THA )  is increasingly being performed in patients with long life expectancies and active lifestyles .
Newer implant bearing surfaces , with superior wear characteristics , often are used in this cohort with the goal of improving longevity of the prosthesis , but comparisons across the numerous available bearing surfaces are limited , so the surgeon and patient may have difficulty deciding which implants to use .
Questions / purpose sThe purpose of this study was to answer the following question : Is there a short- to mid-term survivorship difference between common THA bearings used in patients younger than age 65 years ?