Survival of a cementless pure titanium cup with laser-structured surface

Purpose: So far no clinical results concerning the survival rates of cement less pure titanium cups with laser-structured surfaces exist. This study wa s performed to evaluate our results for the Alphasegment acetabular compone nt (Alphanorm). Method: Retrospective analysis of 50 cups in 45 patients wa s performed (operations performed between November 1995 and January 1998). The average age at the time of the implantation was 65.1 years. Dysplastic hips and revisions were excluded. The survival rate was calculated accordin g to the Kaplan-Meier analysis with the end point defined as the revision s urgery of the cup. Results: The average follow-up period was 2.9 (0.6-4.0) years. Two patients (i.e., two implants) died during the observation period , none were lost for followup. Six of the cups had to be revised due to ase ptic loosening. The survival rate at 3.2 years after implantation was 87%. None of the stems had to be revised. Conclusions: Further use of the cement less hemispherical pure titanium cup with laser-structured surface cannot b e recommended. The observed prevalence of loosening for the Alphasegment ac etabular components was higher than for other cups. Close follow-up of pati ents with this type of implant is necessary.