Femoral head replacement with the christiansen endoprosthesis. A follow-up study, and a report on 175 arthroplasties with the present model of the prosthesis with acrylic cement fixation.

A review of the experience gained after 300 consecutive femoral head replacements using the Christiansen Endoprosthesis is given. The arthroplasties were performed mainly for fresh, displaced femoral neck fractures in elderly patients and for complications of these fractures, such as pseudarthrosis and aseptic necrosis. The patient material is divided into 2 groups. Group 1: Patients who had the older prosthesis model with plastic capitulum pieces inserted, and Group 2: Patients who had the present prosthesis model with metal-capped capitulum pieces inserted together with acrylic cement fixation. While the results initially were promising in the first group, a longer follow-up was very disappointing. Wear of the plastic material resulted in a pronounced foreign body synovitis with pain and reduced mobility. Furthermore, there were osteolysis and fractures related to the prosthesis in a great number of patients observed for more than 2 years. This led to a change in the construction of the capitulum piece of the prosthesis which was now equipped with a metal cap and to the use of acrylic cement fixation of the shaft piece. The follow-up results in these patients (Group 2) have been most encouraging, with absence of the above-mentioned complications after up to 6 years' observation. The mortality and complications encountered are discussed. It is concluded that femoral head replacement on the indications outlined, using the present prosthesis model with acrylic cement fixation, represents a very good alternative in the treatment of displaced femoral neck fractures and their complications.