[Long-term results with the Wagner metal-on-metal resurfacing prosthesis].

INTRODUCTION

Former failures of hip resurfacing arthroplasties in the 1980s were attributed to articulating materials and malpositioning of the implants. To solve these problems in the 1990s metal-on-metal articulations were developed. The purpose of this study was to depict the long-term results of the Wagner resurfacing prosthesis utilising a metal-on-metal surface articulation.

PATIENTS AND METHOD: Between January 1991 and December 1995 40 Wagner resurfacing prostheses were implanted. All operations were performed via an anterior approach. 37 patients were able to be followed up after an average period of 13.1 years. For clinical evaluation the score according to Merle d'Aubigné was used. For radiological assessment X-rays in two planes were evaluated.

RESULTS

On average, 1.45 (1 to 9) preliminary operations were performed on each patient prior to the implantation of the actual surface replacement prosthesis. In 32 cases a cementless femoral component was used, in the remaining 8 cases a cemented one. The score according to Merle d'Aubigné improved from a pre-operative average of 8.3 to a post-operative average of 17.3 points (p < 0.001). 17 of 40 (42.5 %) hip resurfacing arthroplasties have been revised.

DISCUSSION: Taking all aspects into account, the high rate of revisions in this series was attributed to extreme indications for hip resurfacing which would not be considered as standard nowadays. Combined with a stricter indication and an exact, careful operative technique, the metal-on-metal surface replacement of the hip joint may offer an alternative replacement option.