12–16 YEAR FOLLOW UP OF HARRIS-GALANTE-I ACETABULAR COMPONENT IN PATIENTS LESS THAN 50 YEARS OF AGE

Abstract

Introduction: The long-term results of 70 Harris-Galante I uncemented acetabular components implanted in 53 patients who were under 50 years of age at the time of their hip arthroplasty are presented.

Methods: Follow up was both clinical, using Oxford and Harris Hip scores, and radiological. Kaplan-Meier survivorship analysis was performed to calculate the survivorship of the acetabular components. Failure was defined as either liner exchange or acetabular component revision due to aseptic loosening, osteolysis, infection or dislocation.

Results: The mean age of the patients at the time of surgery was 40 years (range 19–49 years), with follow up of between 12 and 16 (mean 13.6) years. All patients’ acetabular components were implanted primarily with cemented femoral components. The mean Oxford Hip Score at the end of the follow-up period was 20 out of 60 (range 12–46) and Harris Hip Score 81 (range 37–100).

At the end of the follow up period, 11 of the 70 acetabular components (polyethylene liner or the acetabular shell) had been revised. The cumulative survival was 94.0% (95% confidence interval 88.4–99.7) with revision of the metal shell as the end point, and 84.0% (95% confidence interval 74.5–93.5) with revision surgery of the acetabular shell or liner due to any reason as an end point. Radiologically, 4 patients require acetabular revision and 22 patients had femoral osteolysis in gruen zone 7, indicative of polyethylene failure. This gave a combined revision, impending revision and zone 7 osteolysis cumulative survival of 55.3% (95% confidence interval 40.6–70.0).

Discussion: In contrast to cemented acetabular components which undergo aseptic loosening and give groin pain, high density polyethylene lined metal shells do not give groin pain but cause silent acetabular and femoral osteolysis. The danger time for osteolysis is between 10–20 years, therefore follow up at that time is essential.