Study of a titanium dual-mobility socket with a mean follow-up of 18 years

Abstract

The concept of stainless steel dual-mobility cup in total hip arthroplasty has demonstrated a very low incidence of long-term instability and a 98% survival rate after 12 years. We systematically implanted titanium alloy dual-mobility acetabular cups during a 5-year period. The purpose of our retrospective study was to report the 18-year clinical results of a homogeneous and continuous series of 103 primary total hip replacements after implantation of a cementless titanium dual-mobility cup. The overall 18-year survival rate of the acetabular cup with a 95% confidence interval was 87.4%. At last follow-up, there was no evidence of implant instability. However, aseptic loosening of the acetabular component was reported in one case and high wear of the retentive liner in nine. The results of this investigation confirmed the long-term stability of dual-mobility implants. The main limitation of this system was early wear of the polyethylene liner in contact with the titanium metal back and third-body reaction associated with loss of the PE liner retentive rim. In our study, titanium demonstrated poor tribological characteristics.