The Fate of Stable Femoral Components Retained During Isolated Acetabular Revision

Background: The decision as to whether to revise a well-fixed femoral component in hips requiring isolated acetabular revision is challenging. The purpose of the present study was to determine the long-term results of, and the complications associated with, retention of a stable and well-fixed femoral component during isolated acetabular revision.

Methods: We retrospectively reviewed the clinical and radiographic results for thirty-one patients (thirty-two hips) who underwent isolated revision acetabuloplasty without removal of a well-fixed femoral component. The reason for acetabular revision was aseptic loosening in thirty-one hips and malposition in one hip. Of the thirty-two femoral components, twenty-one were cemented and eleven were cementless. The average duration of follow-up from the time of the index revision was 8.1 years (range, 6.4 to 12.5 years), and the average duration of total service of the femoral component was seventeen years (range, seven to twenty-five years) from time of the initial implantation. The average age of the patients at the time of the index revision was sixty-six years (range, twenty-nine to eighty-seven years).

Results: Thirty-one (97%) of the primary femoral components were judged to be stable and well fixed at the latest follow-up evaluation. One femoral component (3%) was revised because of aseptic loosening, eight years after the index acetabular revision and seventeen years after the initial total hip arthroplasty. Radiographic evaluation of the thirty-one femoral components that were not revised demonstrated no evidence of loosening or subsidence. There were no dislocations, nerve palsies, or intraoperative fractures associated with retention of the femoral component. Twenty-seven (84%) of the acetabular components were judged to be stable at the latest follow-up evaluation.

Conclusion: In hips treated with isolated acetabular revision, a well-fixed femoral component can be retained successfully without adversely affecting the acetabular exposure; the placement, position, or stability of the acetabular component; or the ability to restore bone stock. The data from the present study support the decision to retain a well-fixed femoral component when the acetabular component needs to be revised.