ACETABULAR RECONSTRUCTION WITH BONE IMPACTION GRAFTING IN REVISION ARTHROPLASTY IN PATIENTS WITH MASSIVE ACETABULAR DEFECTS

Abstract

Introduction: Loosening of acetabular components often lead to excessive bone defects. Managing severe acetabular bone loss in revision arthroplasty is a serious or sometimes even an impossible challenge. Several authors even have published disappointing results. The purpose of this study was to evaluate the long term clinical and radiographic results of acetabular reconstruction with the use of bone impaction grafting and a cemented cup in cases with very large acetabular defects.

Methods: In this historical prospective study, 27 hips (25 patients) with large acetabular defects (AAOS type III and IV, Paprosky type 2B to 3B) were reviewed. In all cases an extensive reconstruction with the use of bone impaction grafting and a large rim wire mesh (Stryker Howmedica, Newbury, UK) was performed. All patients have had a six week bed rest period or 3 weeks of bed rest with 3 weeks of non-weight bearing mobilization. No patient was lost to follow-up. Three patients died during follow-up, the cause of death was in all cases not related to the surgery. All medical files and radiographs were analyzed.

Results: After a mean follow-up of 8.8 years (range 4 to 14.1), 3 hips needed repeat revision and another 2 hips were considered radiographic loose. Reasons for repeat revision were: septic loosening after 4.7 years, aseptic/traumatic loosening after 5.8 years and a broken-out reconstruction after 5 weeks because lack of compliance of the patient.

Kaplan-Meier analysis showed a ten-year survival rate of 87% (95%C.I. 73.1–100%) with end point acetabular revision for any reason and 95% (95%C.I. 86.2–100%) with end point acetabular revision because of aseptic loosening. The mean preoperative HHS was 55 points and improved to 72 points postoperative.

Conclusion: Acetabular reconstruction using impaction bone grafting and a cemented cup can produce favorable long-term results in patients with massive acetabular bone-stock defects. It is the only revision technique which restores massive acetabular bone stock loss. However, in these extensive defects it is a technical demanding procedure and should only be used by surgeons with extensive experience with this technique.