Long-Term Comparison Safety and Outcomes of Simultaneous, Staggered, and Staged Bilateral Total Knee Arthroplasty

Background: The purpose of this study was to determine the safety and the clinical outcome of simultaneous, bilateral, and staged bilateral total knee arthroplasty (TKA) performed by a single surgeon at one academic institute. Methods: We prospectively followed and retrospectively compared the results of 7,155 patients (14,310 knees) who had simultaneous bilateral TKA, 6,671 patients (13,342 knees) who had staggered bilateral TKA, and 4,501 patients (9,002 knees) who had staged bilateral TKA. The mean age of the patients was 67, 65, and 69 years, respectively. The mean follow-up was 15.5, 15.3, and 16.1 years, respectively. The prevalence of mortality and complications were assessed in each group. In addition, patients were assessed clinically and radiographically at each follow-up. Results: The mortality rate (14 patients, 0.2%) of the patients who underwent simultaneous bilateral TKA was similar to those who underwent staggered bilateral TKA (19 patients, 0.3%) and those who underwent staged bilateral TKA (18 patients, 0.4%) (P > 0.05). The major complication (except death) rate (0.8, 0.5, and 0.4%, respectively) and the minor complication rate (20.7, 19, and 19.6%, respectively) were not significantly different among the three groups (P > 0.05). There was no significant difference in the clinical outcomes, radiographic results, revision rate, or survivorship of TKA implants among the three groups (P > 0.05). Transfusion requirements were different among the three groups (10% in the simultaneous bilateral TKA group, 12% in the staggered bilateral TKA group, and 2% in the staged bilateral TKA group). Conclusions: We found no significant differences among the simultaneous, staggered, and staged bilateral TKA groups, with regard to the mortality, major complication, minor complication, and revision rates; the survival of TKA implants; and clinical and radiographic results after a mean follow-up of 15.5, 15.3, and 16.1 years, respectively.