Interlocking acetabular fixation screws and their combination with a reverse hip acetabular cup

摘要

Interlocking acetabular fixation screws having a threaded shaft for threading into cancellous bone and a tapered threaded head for threading into tapered threaded screw holes in a reverse hip acetabular cup. The reverse hip acetabular cup has a central stem and the threaded screw holes are drilled at an angle that allows drilling of the bone of the acetabular cavity, placement of the screws and tightening of the screws without touching the central stem and without interference from the central stem.

主权项

1. A reverse hip acetabular cup having a surface for secure attachment to an acetabular cavity and a concave surface having a central stem extending therefrom,
the acetabular cup and stem having a common first central axis, the acetabular cup comprising at least one threaded screw hole through said acetabular cup, having a second central axis and a circumferential edge on the concave surface wherein lines extending from said circumferential edge and in parallel with the second central axis do not intersect with the central stem, and wherein i) the central stem is solid and has a male Morse taper, and/or ii) the central stem is greater than 7 mm in length, and/or iii) the lines extending from the circumferential edge and in parallel with the second central axis do not intersect with the first central axis prior to intersecting an equatorial plane of the acetabular cup.