Austin Moore cervicocephalic prostheses have been a therapeutical option for femoral neck fractures in patients with a reduced general condition for many years. Since treatments other than total hip arthroplasties have also been included in National arthroplasty registers during the last decade, adequate reference data for comparative analyses have recently become available. Based on a standardised methodology, a comprehensive literature analysis of clinical literature and register reports was conducted. On the one hand, the datasets were examined with regard to validity and the occurrence of possible bias factors, on the other hand, the objective was to compile a summary of the data available. The main criterion is the indicator of Revision Rate. The definitions used with respect to revisions and the methodology of calculations are in line with the usual standards of international arthroplasty registers.Introduction
Materials and Methods
The published results from clinical follow up studies have been compared to Arthroplasty register Results: Results: 24% of all papers were published by the inventor of the implant. These publications show a 3,4 times lower revision rate compared to independent studies and a 4,6 times lower revision rate compared to Register based publications. The cumulative revision rate per 100 observed component years of register based publications is 1,36 times higher compared to independent clinical studies. The difference is statistically not significant. Pooling the published data from all follow up studies the impact of the studies published by the inventor leads to a statistically significant bias.
Arthroplasty Register data are able to detect bias factors and lead to a better quality of assessments concerning the outcome of arthroplasty.
This article considers some of the problems of the interpretation of information from other national arthroplasty registers when setting up a new register. In order for the most useful information to be available from registers much international co-operation is required between all those responsible for the design of registers as well as those who gather, assess and publish the data.
We reviewed 80 patients (87 hips) who were older than 80 years of age at the time of cementless total hip arthroplasty. An Alloclassic SL stem had been implanted in all patients. A variety of cementless acetabular components was used. After a mean follow-up of 69.3 months (39.2 to 94.1) 48 hips in 43 patients were analysed clinically and radiologically. One patient had sustained a traumatic periprosthetic fracture of the femur with subsequent exchange of the stem 73 months after operation. Thirty-two patients (34 hips) had died and five patients (five hips) were unavailable for follow-up because of health reasons (four patients) or lack of co-operation (one patient). If the endpoint is defined as removal of the prosthesis because of aseptic loosening, the survival rate was 100% for the cup and stem after 78 months. The mean Harris hip score was 81.9 points. Radiolucent lines and osteolysis were seldom found.