Surgical case order is associated with postoperative infection risk in total knee arthroplasty

Abstract

Total knee arthroplasty is regarded as the most effective treatment for severe knee joint problems. Surgery case order influences operative outcomes according to previous studies. This study aims to evaluate the effect of surgical case order on operative outcomes for TKA. A retrospective study was conducted on 4,267 TKAs performed by five surgeons at our hospital from May 2008 to December 2018. Variables, such as surgical time, blood loss, and hospitalization stay, were also recorded and analysed. Logistic regression was used to evaluate surgical case order, age, sex, and BMI as factors associated with postoperative PJI. Of the 4267 cases in this cohort, 1531 TKAs were classified as the first case of the day, 1194 TKAs were the second case of the day, 913 TKAs were the third case of the day, 490 TKAs were the fourth case of the day, and 139 were the fifth or later case of the day. The mean operating time was shorter in intermediate cases ( P < 0.01). Postoperative PJI rates increased across later surgical case-order groups ( P = 0.0068). Later case order (OR = 1.29 [95% CI: 1.12–1.49], P < 0.001) was associated with postoperative PJI. The operative time and length of stay were increased for cases performed later in the day. Surgical case order was associated with an elevated risk of postoperative PJI following total knee arthroplasty. Variations in operative time and length of hospital stay were observed across different daily surgical case order, with relatively longer operative time and prolonged LOS observed in third-round or later TKA cases. Our results suggest that daily surgical case order may represent a potential modifiable factor correlated with TKA infection risk, and cases scheduled later in the same operating room may have higher odds of postoperative PJI, but these findings should be interpreted as exploratory and require confirmation in future studies.