RESUMO
To evaluate the clinical effectiveness and complications of large-diameter metal-on-metal prostheses, particularly in the elderly, we performed cementless total hip arthroplasty (THA) using metal-on-metal prostheses with large-diameter femoral heads (mean, 45 mm) in 59 patients (average age, 75.1 years) between January 2004 and December 2005. All procedures were performed using a posterolateral approach and spinal anesthesia. Average follow-up was 65 months. Pre- and postoperative Harris Hip Scores and SF-36 questionnaire results were recorded for all patients to evaluate the level of pain relief, improvement in physical function, and changes in quality of life. Postoperative radiographic images were used to document areas of osteolysis and probable aseptic loosening. Average preoperative Harris Hip Score was 36.1±5.7, compared to 69.4±8.3 at last follow-up (P<.01). Average preoperative SF-36 score was 33.6±7.4, compared to 71.8±6.4 at last follow-up (P<.01). There were no dislocations, aseptic loosening, or revisions. Our findings suggest that metal-on-metal cementless prostheses with large-diameter femoral heads in THA can produce satisfactory results with good durability, a low rate of dislocation and aseptic loosening, and a low incidence of revisions in the short term. The benefits of this technique for elderly patients, especially those with weak muscle power and reduced cognitive function, include avoidance of severe cement-injection complications and early functional recovery.