“…For our cohort, LOS was on average 1.0 and 0.5 days higher in readmitted RKA and RHA patients as compared with controls. In the literature focusing on drivers of LOS after primary or revision TJA, greater age, female gender, BMI, days from admission to operation, preoperative and postoperative mobility (including the 36-item Short-Form Health Survey score and need for walking aids), preoperative and postoperative hemoglobin, need for blood transfusion, and ASA class 3/4 [22][23][24]. In an analysis of 23 919 elective noncardiac surgical procedures, Collins et al [25] found nonwhite race, dependent functional status, age N60 years, ASA class 3/4, and severe adverse events (such as need for reoperation) to be drivers of extended LOS (defined similarly as N 75th percentile LOS).…”