Long-term radiographic evaluation of Trilock press-fit acetabular components in primary total hip arthroplasty.

A retrospective radiographic evaluation of 39 acetabulae reconstructed with Trilock press-fit components (Depuy, Warsaw, IN) without use of supplementary fixation was performed. The following radiographic criteria were evaluated: change in component inclination angle, migration, osteolytic areas, and radiolucent lines. Acetabular components were considered loose when there was migration greater than four millimeters, change in abduction angle greater than four degrees, or a concentric radiolucent line greater than two millimeters. The average length of follow-up was 12.6 years. Six of the 39 (15.4%) total hip arthroplasties were considered loose. Two (5.1%) of these were revised and four (10.4%) were asymptomatic at the time of latest follow-up. Significant areas of osteolysis were found in 15 hips (38.5%). We conclude that the Trilock acetabular component provides adequate fixation and satisfactory long-term results.