Unilateral vs bilateral total knee arthroplasty risk factors increasing morbidity.

Because surgeons are electing to perform simultaneous bilateral total knee arthroplasty (TKA), it is important to identify which patients are at increased risk. We performed a retrospective cohort analysis of 150 patients with unilateral TKA vs 150 patients with simultaneous bilateral TKA. The bilateral group demonstrated a 2.1 times greater mean overall complication rate as well as increased transfusion rates. Patients older than 70 years exhibited significantly higher complication rates. Having a preexisting pulmonary disorder in the bilateral cohort carried nearly a 3-fold risk of complications. Patients with body mass indices greater than 30 displayed a complication rate of 0.97 in the bilateral group as opposed to 0.44 in the control group. Our study demonstrated that age, body mass index, and a preexisting pulmonary disorder resulted in increased complications.