Abstract
Introduction
Patients with osteonecrosis of the femoral head are typically younger, more active, and often require high rates of revision following primary total hip arthroplasty. However, outcomes of revision hip arthroplasty in this patient population have been rarely reported in the literature. The purpose of this study was to report the intermediate-term clinical and radiographic outcomes of revision hip arthroplasty in patients with osteonecrosis of the femoral head.
Materials & Methods
Between November 1994 and December 2009, 187 revision hip arthoplasty were performed in 137 patients who had a diagnosis of osteonecrosis of the femoral head. Exclusion criteria included infection, recurrent instability, isolated polyethylene liner exchange, and inadequate follow-up (less than 3 years). The final study cohort of this retrospective review consisted of 72 patients (75 hips) with a mean age of 53.3 years (range, 34 to 76). Components used for the acetabular revision included a cementless porous-coated cup in 58 hips and an acetabular cage in 2 hips. Components used for the femoral revision included a fully grit-blasted tapered stem in 30 hips and a proximally porous-coated modular stem in 9 hips. The mean duration of follow-up was 7 years (range, 3 to 17).
Results
Mean Harris hip score improved 49 points preoperatively to 90 points. At the time of final follow-up, 11 hips (14.7%) patients required additional reoperation procedure. Of these, six for aseptic loosening of acetabular cup and/or femoral stem, two for deep infection, one for recurrent dislocation, one for periprosthetic femoral fracture, and one for ceramic head fracture. Kaplan-Meier survivorship with an end point for cup revision for aseptic loosening was 98.4% at 5 years, 93.4% at 10 years, and with an end point for stem revision for aseptic loosening was 100% at 5 years, 97.4% at 10 years (Fig. 1).
Conclusions
Unlike the previous report, our study showed lower failure rate of femoral stem after revision hip arthroplasty using modern cementless femoral components in patients with osteonecrosis of the femoral head. Aseptic cup loosening or osteolysis is the most common mechanism of failure at the medium-term follow-up following revision hip arthroplasty in these patients group.
