Abstract
Background This study aimed to identify factors affecting the length of hospital stay (LOS) after total knee arthroplasty (TKA) in patients classified as American Society of Anesthesiologists (ASA) physical status I or II, with a focus on patient-dependent determination of discharge. The goal was to explore strategies to shorten LOS. Methods A retrospective cohort study was conducted on 398 patients (494 knees) who underwent primary TKA. Factors associated with LOS were analyzed, including age, body mass index, operative time, clinical scores, anemia, albumin levels, age group, sex, and ASA physical status. Data are presented as medians (interquartile range). Results The median LOS for all patients was 35 days (range: 29-42 days). Patients aged 80 and over had a significantly longer LOS (39 days; range: 31-45) compared to younger age groups (vs. less than 60s: 32 days (range: 26-37 days), p=0.016; vs. 60s: 33 days (range: 30-38 days), p<0.001; vs. 70s: 35 days (range: 29-43 days), p=0.033). Females also had a significantly longer LOS (36 days [range: 30-43 days]) compared to males (31 days [range: 24-40 days]; p<0.001). Multivariate analysis confirmed that being aged 80 or over (p<0.001) and being female (p<0.001) were significantly associated with longer LOS. Conclusion Postoperative interventions tailored for patients aged 80 years or older and females may be effective in shortening LOS after TKA. A patient-centered approach suggests a maximum LOS of approximately five weeks. Balancing provider-driven early discharge with patient-centered extended stays is crucial for optimizing postoperative care.