Abstract
Background
Highly porous acetabular components are widely used in revision hip surgery. The purpose of this study is to compare the mid-term survivorship, clinical and radiological outcomes of a hemispherical cup (Stryker Tritanium Revision component) and a peripherally expanded cup (Zimmer TM modular component) in revision hip surgery.
Methods
Between 2010 and 2017, 30 patients underwent revision hip replacement using a hemispherical cup and 54 patients using a peripherally expanded cup. The surgery was carried out by two arthroplasty surgeons, both fellowship-trained in revision hip surgery. Kaplan-Meier analysis was used to determine the survivorship of the components. Clinical outcomes were measured using the Oxford Hip Score. Radiographs were analysed for the presence of radiolucent lines in the DeLee and Charnley zones.
Results
Follow up of both components ranged from 2 – 8 years. All the hemispherical cups were reinforced with screws whilst 86% of the peripherally expanded cups required screws. Four (13%) of the hemispherical cups required re-revision surgery for aseptic loosening. One (2%) of the peripherally expanded cups was revised for dislocation, but none for aseptic loosening. None of the peripherally expanded cups exhibited significant radiolucency as compared to 8 (27%) hemispherical cups. The mean Oxford Hip Score of the hemispherical and peripherally expanded cups was 38 and 40 respectively. Using revision for any cause as the end, survivorship of the hemispherical cups at 7.6 years was 80.66% while the peripherally expanded cups at 8.2 years was 98.15%.
Conclusions
In our case-series, a peripherally expanded cup has shown a better mid-term radiological and clinical result, with a lower rate of re-revision surgery, when compared to a hemispherical cup.
