AIM: In this prospective randomised study, the influence of different bearing materials on migration and wear was measured and their effect on the function of the artificial joint and the @entity1 outcome was investigated. Mid-term results were recorded so that recommendations can be made on the use of certain bearings, which minimise wear and thus the danger of subsequent @entity1349 . METHOD: Sixty-six @entity1 met the inclusion criteria and were willing to take part in the study. These @entity1 were randomised to 2 groups. All of them had total hip arthroplasty with implantation of a cementless Bicontact stem and Plasmacup using a cementless press-fit technique. Thirty-five of these @entity1 were given a ceramic-ceramic bearing and 31 @entity1 a ceramic- @entity691 bearing (gamma sterilised/ @entity1568 environment). At the most recent follow-up, they underwent detailed clinical and radiological examination and evaluation by means of the Harris Hip Score, Hannover function questionnaire and single-film X-ray analysis (EBRA). RESULTS: The overall follow-up rate was 65.2 % (43 of 66) and the mean follow-up period was 8.1 (7.1 - 9.2) years. The median Harris Hip Score at the time of follow-up was 90.1 (58.7 - 99.9) points. The average Hannover function score was 87.14 % (63.9 - 100). In 4 of 66 cases (6.1 %) there was a tendency for the Plasmacup to subsidence in the first postoperative months that was slight but detectable by EBRA; however, this stopped subsequently. This primary subsidence was independent of the chosen bearing material. No significant difference in the clinical and radiological parameters was found between the two groups. CONCLUSION: The very good results with regard to the rate of loosening confirm the press-fit cup fixation concept. The study shows a similar medium-term result for the ceramic-ceramic and ceramic- @entity691 bearing so that use of both bearings can continue to be recommended. Only long-term studies with sufficiently large numbers of @entity1 will be able to show whether significant differences can be detected between the two slide bearings with regard to wear and migration behaviour and so that a recommendation can be given to the surgeon.

EBRA migration patterns of the Plasmacup with ceramic or XXXX inserts: a randomised study.

@entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity1568 :: ('MESH:D009584', 'Chemical') :: ['nitrogen'] @entity691 :: ('MESH:D020959', 'Chemical') :: ['polyethylene'] @entity1349 :: ('MESH:D011475', 'Disease') :: ['aseptic loosening']
@entity691 :: (MESH:D020959,Chemical) :: ['polyethylene']
