ABSTRACT
Patients with total knee arthroplasty following patellectomy have been reported to experience pain and instability. The results of sixteen consecutive primary total knee replacements, performed an average of eleven years [range, four to twenty seven years] after a patellectomy in sixteen patients, were reviewed prospectively. The average duration of follow up after the arthroplasty was 5.7 years [range, three to eight years]. The average age of the patients at the time of the arthroplasty was 66.9 years [range, 53-79 years]. There were four men and twelve women. In all patients of this study the posterior cruciate ligament was sacrificed and a posterior stabilized prosthesis was used. All patients were evaluated according to the rating system of the Knee Society. Differences between the preoperative and postoperative [last evaluation] scores were assessed with the student's t-test and chi-square test. The mean overall Knee Society clinical score was improved from 69.1 points preoperatively to 166.2 points at the last follow up evaluation. This improvement was highly significant [p<0.001]. On the basis of the evaluation of the small series included in this study, we believe that total knee arthroplasty using a posterior stabilized prosthesis may represent a safer and more predictably stable choice in patients who have had a previous patellectomy