Triple taper polished cemented stem in total hip arthroplasty: rationale for the design, surgical technique, and 7 years of clinical experience.

Abstract

Successful long-term clinical results with the Charnley low-friction torque arthroplasty have identified proximal femoral strain shielding as a long-term problem to be addressed. The problem has arisen because of the load transfer by a distally supported stem that is no longer subject to fracture. To overcome this problem and improve proximal load transfer to the femur, a continuous triple-tapered stem--the C stem--was designed. This article describes the first 500 primary hip arthroplasties at a mean follow-up of 3 years, 5 months (range, 1-7 years). There have been no revisions for aseptic stem loosening, and no stem is considered to be at risk for loosening. In 20% of cases, there was subjective radiologic improvement of the bone-cement interface.