Technical considerations of cemented acetabular components: a 30-year evaluation.

The effect of porosity reduction cementing techniques with respect to radiolucent lines in Zone 1 and failure in acetabular components was studied in 2,237 consecutive cemented acetabular components done between 1970 and 1998. The minimum followup was 2 years. Radiolucencies in Zone 1 on initial radiographs obtained postoperatively were tabulated for five groups of patients based on cementing techniques. The percentage of loose or revised cups was calculated for six groups based on type of prosthesis used. The lowest percentage of Zone 1 radiolucencies was in a group in which bowl mixing was used. The lowest failure rate was in the group that received Charnley prostheses in which simple first generation cement techniques were used. Porosity reduction techniques did not reduce the incidence of Zone 1 radiolucencies. For the acetabular side of a total hip replacement, the biology of the bone and the techniques of cement insertion that include a dry cancellous bone bed, perforation and removal of peripheral sclerotic areas, pressurization of the entire cement mantle in the socket at one time, and complete burying of the acetabular component within the boundary of the bony acetabulum are the essential factors, not porosity reduction in the cement.