Cementless hemispheric acetabular components. A 4- to 8-year follow-up report.

Overview

A retrospective radiographic analysis was performed on 71 cementless acetabular components followed from 4 to 8 years after surgery. A Harris-Galante (Zimmer, Warsaw, IN) cup was used in 46 cases and an Optifix (Smith & Nephew Richards, Memphis, TN) cup was used in 25 cases. There were 66 primary and 5 revision cases. Nonprogressive radiolucencies were common in both types of cups (64% of Optifix, 70% of Harris-Galante). Radiolucencies were almost exclusively less than or equal to 1 mm in width and were most common in zones 1 and 3. Ten cups had continuous but nonprogressive radiolucencies, none greater than 1 mm in all three zones. No radiolucent lines wider than 2 mm were seen in any case. Four cups had progressive radiolucency that stabilized. Radiolucency around fixation screws was seen in one case, and demonstrated stable ingrowth at revision surgery. No cases of osteolysis, screw breakage, migration, or loss of fixation surface occurred. A single case of a broken locking mechanism of a Harris-Galante cup 2 years after liner exchange is reported.