Mittelfristige Ergebnisse der Knietotalendoprothese Typ Foundation

In the period from May 1993 to December 1995, 263 prostheses were implanted in 249 patients in the orthopedic department of St. Vincentius hospitals in Karlsruhe. Between the end of October 1996 and the end of December 1998 127 patients with 143 implanted prostheses were examined. For 126 patients, the indications were primary gonarthrosis and for 17 patients rheumatoid arthritis, posttraumatic osteoarthritis or a necessary prosthesis change. The pre- and postoperative data were evaluated with the help of the HSS score and the KS score, which were divided into the clinical score and the function score. For this purpose, a separate questionnaire was developed, that included both scores. In addition, patients with primary gonarthrosis were considered separately from those with rheumatoid arthritis, fractures close to the knee joint, and patients with prosthesis changes. The HSS score showed postoperatively very good overall results for a total of 109 patients or prostheses (77%). The difference between the two groups is significant (GA 77% - RA et al., 70.6%). In the clinical KS score, even 118 patients (82%) had excellent and another 15 (10%) good results. More than 75% of the patients in both groups had absolute pain relief with regard to the knee joint. The functional score, that is not influenced by subjective criteria, also showed comparable good to excellent results in both subpopulations (101 (80%) patients from the group of GA and 13 (77%) from the other group). Overall, the results in the function score are better in both groups than in the Knee score. The Knee score showed greater differences between both groups. In the course of radiological follow-up examinations, none of the prostheses showed possible or clear signs of loosening, except for one case of patella failure. The determination of the leg-axis produced the greatest discrepancies between the two scores. Here, a weakness of the HSS score is shown, which does not define the physiological axis of the leg. Nevertheless, the measurement of the axial misalignment is preoperatively one of the most important criteria for the indication of the implantation of a non-constrained knee endoprosthesis. In summary, both groups show significant improvements in both scores in the medium term, combined with a significant increase in the quality of life. The non-constrained knee endoprosthesis Type Foundation has very good functional and stabilizing properties. It thus comes very close to the requirements placed on the physiological biomechanics of a knee joint. Depending on the patient and the position of the implant, the bone-saving implantation technique allows the implantation of a surface glide replacement, possibly also posterior cruciate sparing or posterior sacrificing prosthesis, even after a later replacement of the prosthesis.