LONG-TERM FOLLOW-UP WITH ALUMINA ON ALUMINA TOTAL HIP ARTHROPLASTY

Abstract

Mechanical failure in total hip arthroplasty is usually due to aseptic loosening related to wear particles as seen with polyethylene bearing. Alumina has been proposed for avoiding wear problems. In vitro and mid-term clinical studies showed tribological advantages but early acetabular fixation issues. Since alumina on alumina bearing is currently used with new fixation techniques, updated evaluations of the ancient series are informative regarding the long-term tolerance of alumina in vivo.

In this paper, we investigated 104 consecutive lumina on alumina cemented total hip arthroplasties (CER-VAER-OSTEAL, Roissy, France) implanted 20 years ago in 81 patients (from 1979 to 1983). Alumina femoral head was 32 mm in diameter. Alumina acetabular socket and titanium femoral stem were cemented. The clinical evaluation used Postel Merle d’Aubigné score. Radiological wear and appearance of osteolysis or loosening were noted for establishing actuarial curves. When accessible, histological samples from revision procedures were analyzed.

Six infected cases were not taken into account later. The average follow-up was 11 years, reaching 18 years in 38 cases. Twenty-three hip were revised for changing 23 acetabular sockets, 12 femoral heads, and 1 femoral stem. We noted 1 femoral head fracture, 24 definite ace-tabular loosenings, 12 probable acetabular loosenings, and 3 definite femoral loosenings. Radiological acetabular osteolysis was present in 4 cases, always limited to De Lee zone 1, and associated with loosening. Radiological wear was below eye detection. Peri-prosthetic tissue showed non-specific histological reaction to cement particles. Survival rate at 20 years was 61.4% in term of revision (57.1% and 95.2% concerning acetabular and femoral defininte loosening).

Beside the high rate of cemented fixation failure of the socket, loosened and non loosend cases showed an excellent tolerance of alumina on alumina bearing in the long-term, with minimal wear and osteolysis. This may also have protected the femoral component from complications.