Removing large diameter acetabular cups with the Explant Acetabular Cup Removal System: A technique to maintain the centre of rotation

Removal of bonded, uncemented acetabular cups is challenging for orthopaedic surgeons, as excessive bone loss or acetabular fracture can compromise the fixation of the revision component. To prevent complications, the Explant Acetabular Cup Removal System (Zimmer, Warsaw, IN, USA) uses a pivot head to find the centre of rotation of the acetabulum, guiding a cutting blade precisely around its curvature. In large acetabular cups, such as those used in metal-on-metal hip replacements, the pivot head used to fix the centre of rotation is too small. We describe a technique using the femoral head from the old prosthesis and the foil from a suture pack to centre the device and maintain an accurate centre of rotation.