Alumina on alumina versus metal on conventional polyethylene: a randomized clinical trial with 9 to 15 years follow-up.

We report the long-term results of a randomized clinical trial that compares, in total hip arthroplasty in a young population, metal-on-conventional polyethylene and alumina-on-alumina ceramic bearings. One hundred and forty hips in 116 patients were randomized. Re-operation, revision rate, clinical scores, and radiological signs of osteolysis and loosening were compared at average follow-up of 123 (9-15) years. At final FU, 107 hips were available for clinical evaluation. Eight (11.6%) revisions were performed in the polyethylene group versus 1 (1.4%) in the ceramic group (p = 0.017). All revisions in the polyethylene group were related to bearing wear: 4 for aseptic loosening with severe osteolysis, 1 for polyethylene induced compressive granulomatous tumor, and 3 for severe liner wear. The only revised case from the ceramic group was secondary to mechanical stem loosening. Mean annual polyethylene wear was 0.19mm/year; wear was not measurable in the ceramic group. Our study confirms, in the long-term, the superiority of ceramic-on-ceramic pairing in comparison to metal-on-conventional polyethylene and supports their use in young, active patients.