Ten-year follow-up of a bicondylar unlinked knee endoprosthesis with particular reference to mid-term results

This analysis, submitted retrospectively, evaluates 603 PCA-type or Duracon-type knee endoprostheses implanted in 527 patients over a 10-year period. In addition, the X-rays available in a group of 138 patients (100 women and 38 men) from the entire patient population were analysed. All of these 138 patients were invited to come in for a follow-up examination. The invitation was accepted by 80 patients. As well as radiological and physical examination, these patients were asked about their subjective physical condition in a semi-open questionnaire. The data obtained by the questionnaire is discussed in the Results section. The average age of the 397 women, of whom 61 were operated on in both knees, and 130 men, of whom 15 were operated on in both knees, was 68 years at the time of the operation. The 76 bilateral patients had the knee endoprostheses implanted within a mean interval of 17 months. The most frequent indications for surgery were primary and secondary gonarthrosis, followed by rheumatoid arthritis. The evaluation of the X-rays from the above population of 138 patients revealed no radiological signs of loosening. No correlation between the time after implantation and the formation of radiolucent margins could be established. Those knee endoprostheses which were implanted with a varus deviation of more than 10 degrees did not yield a poorer result than those implanted perpendicular. In comparison with the cemented implants, the cementless implants produced slightly better results.