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 ?
THA With Delta Ceramic on Ceramic: Results of a Multicenter Investigational Device Exemption Trial
Although the published studies on the outcomes of  total hip arthroplasty (  THA ) performed with currently available ceramic components show high survivorship and low bearing wear at midterm followup , concern over ceramic fracture and squeaking persist . For these reasons , the use of ceramic is limited . Recently , a new alumina matrix composite material ( Delta ceramic ) with improved material properties was developed to address these concerns . We report the early outcomes and complications of a prospect i ve , r and omized , multicenter trial of 263 patients ( 264 hips ) at eight centers , comparing a Delta ceramic-on-ceramic ( COC ) articulation with a Delta ceramic head-crosslinked polyethylene bearing combination ( COP ) . There were 177 COC hips and 87 COP hips . Complications  were reported for all patients , whereas  clinical and radiographic results were provided for the 233 patients with minimum 2-year followup ( average , 31.2 months ; range , 21–49 months ) . The Harris hip scores and clinical , radiographic , and survivorship outcomes were similar in both groups . There were four ( 2 % ) revisions in the COC group and two ( 2 % ) in the COP group . We encountered three intraoperative ceramic liner-related events . In addition , one patient receiving the COC underwent revision for chipping of the ceramic liner , and a second had ceramic fragmentation on followup radiographs but has not undergone revision . These liner related complications remain a concern . No patient reported squeaking in either group ; this leaves us hopeful the new material will lessen the frequency of squeaking . In the short term , the Delta COC articulation provided similar functional scores and survivorship and complication rates with the ceramic head mated with crosslinked polyethylene . Level of Evidence : Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence
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 ?