[Initial experience using the new Weill cementless threaded ring in acetabulum replacement]

First experiences with a new threaded ring for acetabulum arthroplasty developed by D. Weill are reported. These experiences are based on 59 implantations, whose clinical courses and complications are lined out. The Weill acetabular arthroplasty turned out to be a very valuable device for both primary and revision hip arthroplasty. It provides all advantages of cementless fixation. The fixation is gained by a selftapping thread on the outside of the titanium ring. Thus a very high primary stability is achieved. A bone grafting possibility in the fossa region is provided. The relative less tolerance of the Weill ring concerning improper orientation predisposing to dislocation is a disadvantage as we experienced.