Effect of Season on Patient-reported Outcomes and Discharge Disposition in Total Hip and Knee Arthroplasty.

INTRODUCTION: Total joint arthroplasty (TJA) is the benchmark for the surgical treatment of osteoarthritis. As TJA is elective, timing can be influenced by patient-specific and environmental factors. Although previous studies focused on complications and readmissions, few have looked at patient-reported outcome measures (PROMs). In the Northeast, cold weather and higher rates of seasonal affective disorder may influence patient satisfaction postoperatively. Given the link between depression and poorer TJA outcomes, this study explores whether season of surgery affects outcomes while accounting for mental health diagnoses.

METHODS: A retrospective single-center review of patients who underwent primary total hip or knee arthroplasty (THA/TKA) between January 2019 and May 2024 (10,989 THA, 12,399 TKA) was done. Seasons were defined meteorologically. Patient demographics, comorbidities, surgical characteristics, discharge disposition, length of stay (LOS), and PROMs (baseline, 3, 6, 12, and 24 months) were analyzed. Multinomial regression and multivariable linear regression assessed the effect of season on discharge and LOS. A fixed-effects model analyzed changes in PROMs over time.

RESULTS: Fall surgeries had the shortest LOS (THA: 0.85 days, TKA: 1.05 days; P < 0.001). Longer LOS was linked to spring/summer surgeries and depression. Fall also had the lowest inpatient rehabilitation discharges (THA: 7.3%, TKA: 8.6%), and season was a predictor of discharge disposition in TKA but not THA (P < 0.001). Baseline PROMs were highest in fall, with lower baseline pain scores and higher baseline function scores. THA patients had greater improvements in HOOS JR and VAS24 scores after spring/summer surgeries (P = 0.01).

CONCLUSION: Seasonality affects LOS and discharge disposition, especially in TKA. Although baseline PROMs varied by season, postoperative improvements were minimally affected. Seasonal factors seem to influence short-term outcomes but have limited long-term effects on patient recovery.