Abstract
In order to avoid the consequences of polyethylene wear in a high-risk population, 128 alumina-alumina total hip arthroplasty were implanted in 116 consecutive patients of 40 years old or less. Osteonecrosis and sequellae of congenital hip dislocation were the main etiologies representing 71% of the hips. The same titanium alloy cemented stem was implanted in all hips. Four alumina acetabular component fixations were used: cemented plain alumina socket (41 hips), screw-in ring with an alumina insert (22 hips), a press-fit plain alumina socket (32 hips) and a press-fit titanium metal back with an alumina insert (33 hips).
Eight patients (11 hips) died during the follow-up period. Sixteen revisions were documented, 12 for ace-tabular aseptic loosening, 3 for bipolar loosening (2 were septic), and 1 for unexplained pain. Eighty-nine hips were followed radiologically for two to twenty years. No femoral nor acetabular osteolysis were observed with an average follow-up of 8.4 years. Wear was unmeasurable. Four additional sockets showed definite migration. The respective survival rate at 7 years were 91.4% for the cemented cup, 88.8% for the screw-in ring, 95.1% for cementless press-fit plain alumina socket and 94.3% for the metal-back press-fit component.
The ten-year survival rate was 88.0% for the cemented socket and 88.8% for the screw-in ring. The fifteen-year survival rate was 76.7% for the cemented socket. The occurrence of a graft was the only prognostic factor with a 62.6% survival rate at ten years for the grafted hips and a 90.1% for the non-grafted hips (p=0.004).
The alumina-alumina bearing surfaces for young patients appeared as a valuable alternative to standard metal-polyethylene system. There is a need to improve socket fixation if we want to have a survival of the arthroplasty as long as the life expectancy of this increasing and demanding population. The last design with a fully coated HA titanium shell and an alumina liner seems to fulfill the requirements.
The abstracts were prepared by Orah Naor. Correspondence should be addressed to him at the Israel Orthopaedic Association, PO Box 7845, Haifa 31074, Israel.
