Cementless acetabular fixation with and without screws: analysis of stability and migration.

The purpose of this study was to compare initial stability and late migration of 775 cementless acetabular components with and without screw fixation. Screw fixation was used in 509 cups and no screws in 266 cups. Average follow-up in the screw fixation group was 6.32 years (range, 2-10 years) and 6.9 years (range, 2-10 years) in the no-screw group. One component (0.2%, osteolysis) in the screw group and one (0.4%, loss of fixation) in the no-screw group required revision. Osteolytic lesions more than 4 cm(2) were noted in 8 (1.6%) screw fixation cups and 2 (0.75%) no-screw fixation cups. No cups in either cohort had radiographic evidence of migration. Screw fixation did not have a favorable or adverse effect on the outcome of acetabular reconstruction.