Survivorship of polyethylene liner exchanges performed for the treatment of wear and osteolysis among porous-coated cups.

For the past 17 years, we have favored treating patients with polyethylene wear and osteolysis by performing a liner exchange with retention of the old shell when possible. Using our institutional database, we identified 187 acetabular revisions in which we had retained the old shell. Among this group, we found 25 rerevisions. These included 10 for hip instability, 9 for cup loosening, 3 for recurrence of excessive wear or osteolysis, 2 for infection, and 1 for dissociation of the replaced liner. The need for rerevision varied with the different retained shell designs. We rerevised 17% of the total hip arthroplasties with old spiked shells, 21% with Arthropor shells, 13% with Triloc shells and 5% with Duraloc shells. Before making a decision to retain or remove a well-fixed old acetabular shell, we recommend consideration of the design's past track record and careful inspection of the condition of the existing shell.