To remove a damaged acetabular cup attached to the hipbone, applicant positions the cutting surface of a curved cutting blade at the acetabular cup/hipbone interface. The blade mounts to a head. The powered drive shaft of a motor rotates the blade and head. A linkage, part of which may be around the drive shaft, moves longitudinally relative to the drive shaft under surgeon control. The linkage pivots the head and urges the blade into the interface. As the power tool rotates the curved blade and the linkage pivots the blade into the interface, the blade follows the hemispherical contour of the interface. Continued powered rotation of the drive shaft and blade and further pivoting of the blade cuts the cup from the hipbone.