Eliminating patellofemoral complications in total knee arthroplasty - Clinical and radiographic results of 121 consecutive cases using the Duracon System

This study reports the minimum 5-year follow-up of our experience with the Duracon Total Knee Arthroplasty System. A total of 121 consecutive total kn ee replacements using the Duracon system (Howmedica, Rutherford, NJ) were p erformed in 104 patients. Three patients died before the 5-year follow-up a nd were excluded from the final evaluation. The remaining 118 knees (101 pa tients) were assessed at a mean follow-up of 65 months (range, 60-80 months ). The knee diagnoses were osteoarthritis in 97 patients, rheumatoid arthri tis in 2 patients, osteonecrosis in 1 patient, and pigmented villonodular s ynovitis in I patient. The mean age was 70 years (range, 28-85 years). Ther e were no reoperations for aseptic loosening, and there have been no reoper ations for patellofemoral problems. At final follow-up evaluation, 112 knee s (96%) had good or excellent results, and 6 knees (4%) had poor clinical r esults or went on to revision. For the surviving knees, the preoperative Kn ee Society objective score improved from a mean of 52 points (range; 20-72: points) to a final follow-up mean of 94 paints (range, 66-100 points). Five knees needed reoperations: 2 knees in I patient because of acute hematogen ous infection at 12 months, 1 knee because of a supracondylar femur fractur e, 1 because of a patellar tendon rupture, and 1 to increase polyethylene t hickness because of instability. The lack of aseptic loosening at the minim um 5-year follow-up compares favorably with any cemented or cementless seri es of knee replacement. The almost complete absence of patellofemoral compl ications in this series also indicates that the design changes, with partic ular attention to the trochlea design and patellofemoral contact throughout full flexion,have achieved their intended purpose. The results are encoura ging at midterm, awaiting true long-term (15-20 years) follow-up.