The premature failure of the Charnley Elite-Plus stem.

Correspondence We welcome letters to the Editor concerning articles which have recently been published. Such letters will be subject to the usual stages of selection and editing; where appropriate the authors of the original article will be offered the opportunity to reply. Letters should normally be under 300 words in length, double-spaced throughout, signed by all authors and fully referenced. The edited version will be returned for approval before publication. Sir, We read with interest the article by Hauptfleisch et al 1 in the Feb-ruary 2006 issue entitled 'The premature failure of the Charnley Elite-Plus stem: a confirmation of RSA predictions'. The authors found that the survival of Elite-Plus femoral components at ten years was 83%, dropping to 59% when stems deemed radiologically loose were included. In a subgroup of 19 components, a roentgen stereophotogrammetric analysis (RSA) had correctly predicted the failure of four. Blame for the poor survival rate was apportioned to the design of the prosthesis. Compared with the Exeter hip, they consider it to be less 'forgiving', requiring 'perfect' cementing to ensure a good long-term outcome. 2 We have carried out a three-year RSA study of 25 Elite-Plus femoral components and have only one potential failure (paper in preparation). Additional measurements or assessments, which we believe are essential in order to judge the cause of failure, 3 were not carried out by the authors. In particular, Barrack, Mulroy and Harris 4 cementing grades were not assessed and so we do not know whether the radiolucencies found at ten years were present post-operatively. The authors have published three papers on RSA of the Elite-Plus, 5-7 but this is the first time that they have revealed that low-viscosity cement had been used in all cases. It is surprising that the authors did not refer to the paper by Walton et al 8 (published in this journal four months before they submitted their paper) which showed that the Elite-Plus performed significantly worse with low-viscosity cement than with high-viscosity cement. This finding is in line with studies of the Norwegian Arthroplasty Register which showed an increased failure rate of the Charnley hip associated with low-viscosity cement. 9,10 Low-viscosity cements such as Sul-fix and CMW3 are no longer used in Norway and Sweden. 10 The authors reject the possibility that cement or surgical technique might be the cause of the high failure rate because they used the same cement and technique on …