[Pathological findings in tissue surrounding revised metal/metal articulations].

INTRODUCTION

The aim of the current study was to elucidate the incidence of allergic reactions to metal/metal articulations in revised total hip arthroplasties.

MATERIALS AND METHODS

Between 1 January 1997 and 31 January 2002 a consecutive series of tissue samples from 13 revised total hip arthroplasties with metal/metal articulations were histopathologically examined for signs of delayed type hypersensitivity (DTH). Mean age at the time of revision of the eight women and five men was 58.7 years. The prostheses were revised after a mean follow-up of 45 months. Indications for revision were progressive osteolysis of the proximal femur in 12 cases and instability in one case. All patients were clinically and radiologically evaluated after a mean follow-up of 52 months (min. 22, max. 74) after revision.

RESULTS

No signs of infection were found in either histopathological or microbiological examinations. In ten cases, perivascular lymphocytic infiltrates could be found as a sign of DTH. After revision and changing of the articulation all osteolyses healed.

CONCLUSION

In 10/13 cases (76.9%) signs of DTH could be detected. The fact that all osteolyses healed after changing the articulation may give a strong hint that there is an immunological contribution to this radiological changes. Metal/metal articulations cannot be recommended as the optimum implant for young patients, as the number of patients with allergic reactions to nickel, chrome or cobalt is increasing continuously.