43. CEMENTLESS TOTAL HIP ARTHROPLASTY FOR RHEUMATOID POLYARTHRITIS: 63 CASES WITH MEAN 8.5 YEARS FOLLOW-UP

Abstract

Purpose of the study: In rheumatoid arthritis, 15 to 28% of patients present hip involvement, sometimes requiring arthroplasty. The purpose of this work was to evaluate the usefulness of cementless implants for patients with inflammatory hip disease, recognising that cemented implants are widely used for this indication.

Material and method: The was a retrospective series of 63 consecutive first-intention cementless total hip arthroplasties (THA) implanted from April 1986 to June 2007 in 48 patients (35 females), mean age 55 years (range 19–87), with rheumatoid arthritis. The majority of these patients were on a two-drug regimen of corticosteroids and methotrexate. Twelve patients were taking anti-TNF alpha. In all cases, both the femoral and acetabular elements of the implant were inserted without cement. The Postel-Merle-d’Aubligné (PMA) score was used for clinical assessment (preop, postop, last follow-up). Signs of loosening were noted on the plain x-rays.

Results: Mean follow-up was 103 months (range 12–264). There was a significant improvement in the PMA score. There were two intraoperative complications (calcar fissuration). Twenty-one cases (33%) exhibited acetabular protrusion requiring autologous bone graft. At last follow-up, all acetabular grafts were incorporated. At last follow-up there were no cases of deep infection. Three cases (4.8%) required uniplar acetabular revision for aseptic loosening at 127, 145, and 217 months after initial implantation. Major wear of the polyethylene insert was observed in all hips, associated with retroacetabular osteolysis. A new cementless implant was used for the revision in two cases, with satisfactory outcome a mean 41 months from revision. In addition, four cups and three stems presented unchanged lucent lines and had not been revised at last follow-up.

Discussion: THA is a therapeutic option for the rheumatoid hip. Long-term outcome with cemented THA has shown an increased incidence of deep infections and aseptic loosening in this context. At mean 9 years follow-up, we have had very encouraging results with cementless implants in this context.