Wear and periprosthetic osteolysis in a match-paired study of modular and nonmodular uncemented acetabular cups

The wear and prevalence of periprosthetic osteolysis at 5 to 8 years of follow-up of the Trilogy cup, which has a modular liner assembled during surgery, was compared with the Implex cup, which has a fixed liner preassembled at the factory. Sixty-three patients (65 hips) with a Trilogy cup and 64 patients (65 hips) with an Implex cup were match-paired for sex, age, height, weight, and diagnosis (osteoarthritis). All patients had a cemented stem with a 28-mm head and a successful clinical and radiographic result. After an average follow-up of 5.65 years, radiographs were studied to determine the total penetration, using the Livermore technique, and the presence of osteolysis. The average total wear in the Trilogy group was 0.47 mm (range, 0–1.95 mm); for the Implex cup, it was 0.43 mm (range, 0–1.45 mm) (P.99). One patient in each group presented with periacetabular osteolysis (P.99). There was no difference in the wear rate and prevalence of periprosthetic osteolysis between the 2 groups.