The Balgrist hip socket for fixation without cement: analysis of 387 primary total hip replacements.

The results of 387 primary hip arthroplasties in which an uncemented Balgrist hip socket had been used in 346 patients were reviewed after a maximum of six years. The mean age of the patients at the time of operation was 54.3 years. Acetabular deficiency according to the AAOS classification was found in 21% of these primary arthroplasties. Three acetabular components (0.77%) had been revised. Using Kaplan-Meier survivorship analysis, with the use of prosthesis revision as the endpoint of failure, the survival rate at five years was found to be 99%. Four acetabular components (1%) had migrated and lysis of bone around the component in zone III occurred in one patient (0.26%). The data suggest that the unique socket design of the Balgrist hip socket (consisting of two tapered parts: an expansive outer titanium-alloy split ring and an insert of polyethylene) provides very satisfactory clinical results with various acetabular defects.