Threaded cup acetabuloplasty. Early clinical experience

Loosening of the acetabular cup component in total hip arthroplasty (THA) remains a source of ongoing concern. Threaded cup acetabuloplasty (TCA) utilizes torque and compression to gain purchase of the acetabular cup into the bony margin of the acetabulum. In an earlier study of 121 patients who had THA with TCA, patient assessments and roentgenograms were examined at an average of 30 months after surgery. Twenty percent of the cases were carried out for failed arthroplasty and 20% of the procedures required bone-graft reconstruction. A 22% incidence of moderate to severe postoperative pain, a 3% incidence of cup dislodgement, and a 24% incidence of radiolucencies between 1-2 mm were observed. The four cup dislodgements occurred in patients with severe osteopenia or in those requiring extensive bone-graft acetabular reconstruction. Good clinical results were obtained for osteoarthritic patients treated with primary THA. These early findings suggest that there is no advantage, but there are possible disadvantages, to threaded cup acetabuloplasty when compared to cup fixation with cement.