IntroductionAs part of 10-year documentation using the Columbus system, the interim evaluation was carried out 5 years after implantation with a collection of clinical scores, evaluation of radiological imaging and collection of statistics concerning complications.MethodsThere was a multicentre prospective recruitment of consecutive patients with the indication of implantation of a surface replacement prosthesis (Columbus CR, Deep Dish fixed inlay). Preoperatively, clinical scores were recorded (KSS and Oxford score). Five years postoperatively a new evaluation of clinical scores, the range of motion (ROM) and a radiological check-up including full leg imaging under load was performed. During this period, detailed complication documentation was made.ResultsA total of 210 patients were recruited in five centres. 187 patients were available for examination 5 years after surgery. Cumulative KSS increased from 87.5 (±26.6) preoperatively to 170 (±29.1) 5 years postoperatively. The cumulative KSS improvement was 81.5 (±35.2) points and was highly significant (p?<?0.0001; t?test). The average functional improvement in the Oxford score between the preoperative and 5?year follow-up was 21.7 (±8.8) points and was also highly significant (p?<?0.0001). The ROM improved from 106.3° (±20.2) preoperatively to 114.0° (±12.1) 5 years postoperatively (p?<?0.0001; t test). Five years after implantation, the average mechanical leg axis was 178.0° (±2.1). There was no clinically apparent or native radiologic visible aseptic loosening of the femoral or tibial joint component. There were 33 complications, but no implant-related complications such as inlay dislocation, material fracture or aseptic loosening. In total, 6 revision surgeries were performed during the follow-up period, which corresponds to a survival rate of 97.1% (CI 95%) for the implanted Columbus knee in the present patient collective for 5 years.ConclusionThe interim analysis at 5 years of long-term observation of the Columbus system provided good clinical and radiographic results. |
