RESUMO
BACKGROUND: The isolated liner and head exchange procedure has been an established treatment method for polyethylene wear and osteolysis when the acetabular component remains well fixed. In this study, the mid-term results of this procedure were evaluated retrospectively. METHODS: Among the consecutive patients operated on from September 1995, two patients (three hips) were excluded because of inadequate follow-up, and the results of remaining 34 patients (34 hips) were evaluated. There were 20 men and 14 women with a mean age of 49 years. A conventional polyethylene liner was used in 26 cases and a highly cross-linked polyethylene liner was used in eight cases. In three cases, the liner was cemented in a metal shell because a compatible liner could not be used. RESULTS: After a follow-up of 5 to 20.2 years, re-revision surgery was necessary in 10 cases (29.4%): in eight for wear and osteolysis at 55 to 101 months after liner exchange and in two for acetabular loosening at 1 and 1.5 years after liner exchange. Re-revision surgery included all component revision (four cases), cup revision (four cases), and liner exchange (two cases). In all re-revision cases, a conventional polyethylene liner was used initially. There was no failure in the cases in which a highly cross-linked polyethylene liner was used. CONCLUSIONS: The results of this study suggest that isolated acetabular liner exchange is a reasonable option for wear and osteolysis when the metal shell is well fixed. More promising long-term results are expected with the use of highly cross-linked polyethylene liners.