Length of stay and inpatient charges of total knee arthroplasty in China: analysis of a national database

Background: There are limited data on the resource utilization of total knee arthroplasty (TKA) in China. This study aimed to examine the length of stay (LOS) and inpatient charges of TKA in China, and to investigate their determinants.Methods: We included patients undergoing primary TKA in the Hospital Quality Monitoring System in China between 2013 and 2019. LOS and inpatient charges were obtained, and their associated factors were further assessed using multivariable linear regression.Results: A total of 184,363 TKAs were included. The LOS decreased from 10.8 days in 2013 to 9.3 days in 2019. The admission-to-surgery interval decreased from 4.6 to 4.2 days. The mean inpatient charges were 61,208.3 Chinese Yuan. Inpatient charges reached a peak in 2016, after which a gradual decrease was observed. Implant and material charges accounted for a dominating percentage, but they exhibited a downward trend, whereas labor-related charges gradually increased. Single marital status, non-osteoarthritis indication, and comorbidity were associated with longer LOS and higher inpatient charges. Female sex and younger age were associated with higher inpatient charges. There were apparent varieties of LOS and inpatient charges among provincial or non-provincial hospitals, hospitals with various TKA volume, or in different geographic regions.Conclusions: The LOS following TKA in China appeared to be long, but it was shortened during the time period of 2013 to 2019. The inpatient charges dominated by implant and material charges exhibited a downward trend. However, there were apparent sociodemographic and hospital-related discrepancies of resource utilization. The observed statistics can lead to more efficient resource utilization of TKA in China.