Improving Safety of Bilateral Knee Arthroplasty: Impact of Selection Criteria on Perioperative Outcome

Abstract

Background: Bilateral total knee arthroplasty (BTKA) procedures are associated with an increased risk of complications when compared with unilateral approaches. In 2006, in an attempt to reduce this risk, our institution implemented selection criteria that specified younger and healthier patients as candidates for BTKA. Questions/Purpose: We sought to investigate the effect of these selection criteria on perioperative outcomes. Methods: In a retrospective cohort study, we used institutional data to identify patients who underwent BTKA between 1998 and 2014. Patients were divided into 2 groups: those who underwent surgery before the 2006 introduction of our selection criteria (1998–2006) and those who underwent surgery after (2007–2014). Groups were compared in terms of demographics, comorbidity burden, and incidence of perioperative complications. Regression analysis was performed, calculating incidence rate ratios to evaluate changes in complication rates. Results: Before the selection criteria were implemented in 2006, patients who underwent BTKA were older and had a higher comorbidity burden. The rate of major complications per 1000 hospital days decreased from 31.5 in 1998 to 7.9 in 2014. A reduction in cardiac complications was the most significant contributor to this decrease in major complications. Conclusion: After stringent criteria for BTKA candidates were implemented at our institution, selection of younger patients with lower comorbidity burden was accompanied by a reduction in the incidence of operative complications. This suggests that introducing such criteria can be associated with a reduction in adverse perioperative outcomes.