More failures of uncemented acetabular screw-rings than of cemented polyethylene cups in total hip arthroplasties

The results of 498 total hip arthroplasties were, prospectively studied. In 329 patients a cemented acetabular polyethylene cup was inserted. In 169 p atients a threaded socket: without cement was introduced. Followup ranged f rom 6 to 8 years and follow-up rate was over 90%. Of the 169 threaded socke ts 8 required revision (4.7%), and 3 acetabular components were seen to be loose on X-ray. Of the cemented cups, only 2 (0.6%) required revision and n one were considered loose on X-ray.