Abstract
Introduction
Patients under the age of 50 who undergo a total hip arthroplasty (THA) are at high risk for wear-related complications due to their higher activity level. Previous studies have shown that highly crosslinked polyethylene (HXLPE) is more durable with no evidence of loosening compared to conventional polyethylene due to its improved wear characteristics. Unfortunately, there are few studies with long term follow-up of HXLPE in this patient population. The purpose of this study was to evaluate two questions related to this population of patients undergoing THA. First, what were the clinical outcomes for HXLPE in patients 50 years or younger at an average follow-up of 15 years? Second, was osteolysis observed in any of these hips?
Methods
Between November 1999 and April 2005, 105 THAs were performed for 90 patients 50 years of age or younger (mean, 42 years; range, 20–50 years). The mean body mass index (BMI) was 30 kg/m2 (range, 17–51 kg/m2). The mean follow-up was 15.25 years (range, 12–19 years). Eight patients (two bilateral) were lost to follow-up, which left 82 patients with 95 hips for analysis. HXLPE was the acetabular bearing for all hips. Harris Hip Scores were collected from all patients. Radiographs were obtained on all patients to evaluate for wear and osteolysis.
Results
Clinical outcomes show excellent results in 81 hips, good results in ten, fair results in three, and a poor result in one hip using the Harris Hip Score. There have been no revisions, infections, or dislocations in this cohort of patients. Fourteen hips developed radiolucent lines in zone I, II, or III of the acetabulum, but none were circumferential. Two hips developed radiolucent lines in zones I and VII in the femur. None of the hips in our study developed osteolysis.
Conclusions
The use of HXLPE in patients under the age of 50 who undergo THA shows excellent clinical and radiographic results at an average of 15 years follow-up.
