Introduction: Wear performances and fracture toughness of the alumina-matrix composite (AMC) Biolox-delta^® are pointed out in the literature. Clinical and radiological studies are needed to assess the potential benefits of AMC/AMC bearing surfaces. The aim of this study is the prospective evaluation of complications and risk factors in patients implanted with AMC liners and 32–36 mm AMC femoral heads.

Methods: 323 consecutive patients were included prospectively since 2006.

243 were implanted for primary surgery with 32 or 36 mm ball heads for a 10–12, 6° tapers.

In 80 cases, we used 32 and 36 mm Delta^® sleeved heads (M,L,XL) for the adaptation on 12–14,5°43 tapers or 10–12, 6° tapers (acetabular revisions in absence of stem exchange, or to increase the lenght of the femoral neck and the offset) All the clinical and radiological files were evaluated at a minimum 2 years follow-up with a special attention for the fracture risk and squeaking. Radiological data were analysed using Dicomesure^® software.

Results: We did not face any significant problem in this series. No fracture occurred. No abnormal wear or implants migration could be detected. We did not observe squeaking phenomenons. 2 THP were revised for septic complications ; the retrivials were analysed for transformation studies(Xray diffraction method XRD). The phase transformation tetragonal to monoclinic was mild, in accordance with previous experimental data.

Conclusion: The limitation of this study is its short follow-up; nevertheless the clinical results are in accordance with the previously published experimental data.