Metal on metal型人工股関節置換術の短期成績

抄録

One hundred and fifty one total hip arthroplasties using metal on metal hip joints were followed at a mean of 4 years (range 1.6 to 6 years) . The average JOA score before operation was 43.5 and at follow-up the average score was 87.4.
Radiographic findings of the incidence of partial radiolucent lines around the components: at the acetabular components, no radiolucent lines were observed, at the femoral components, they were seen in 8.6% (13 hips) . Cortical hypertrophy was observed in a high proportion, of 27.2% (41 hips) . There was no loosening, nor component tilt over 5°, observed in any patient. Post-operative dislocation of the hip was observed in 9 hips (6.0%) .
Cobalt and chromium concentrations in serum were measured in metal on poly and metal on metal total hip arthroplasty patients and in controls without implants. Serum was assayed using graphite furnace atomic absorption spectrophotometry. No patients were found to have elevations in serum cobalt and chromium concentrations.
The authors conclude that metal on metal joints showed excellent results at short-term follow-up.