OBJECTIVES:

This study aimed to understand trends in the cost of total knee arthroplasty (TKA) in the U.S. from 2000 to 2021 from the hospital perspective.

METHODS:

The PREMIER Healthcare Database (2000–2021) was analyzed for total and department costs for patients that underwent primary TKA (N=1,841,541) over time. All costs were inflation-adjusted to 2021 USD. Generalized linear models with log link function were used to examine the association between race and cost of TKA adjusting for patient demographics, marital status, insurance type, admission year, pre-operative characteristics, intra-operative characteristics, and provider characteristics.

RESULTS:

In 2000, the mean total cost for one TKA episode was $22,551 (SD=$9,571). By 2020, the total cost decreased to $15,908 (SD=$7,296). Supply cost and operation room cost were the largest two among all department costs (46% and 25% of mean total cost of all the years). From 2001 to 2021, outpatient and inpatient cost for TKA decreased by 33% and 25%, respectively. Lab cost reduced by 87% for outpatient and 71% for inpatient. Supply cost reduced by 30% for outpatient and 36% for inpatient. Operating room cost for both outpatient and inpatient slightly increased over the years. For both Black and White patients, total cost increased from 2000 to 2006 and gradually decreased thereafter. However, total cost, lab cost, operation room cost, and radiology cost were constantly higher for Black patients compared to Whites. In the adjusted model, the total cost of TKA for Black patients was 1.05 times (95% CI: 1.049, 1.055) the total cost for Whites, with a marginal effect of $1022.

CONCLUSIONS:

Hospital costs associated with primary TKA have decreased over the years, coupled with the shift from inpatient to outpatient, with largest decrease in lab cost and supply cost. However, Black patients are likely to have higher total bill cost than White patients in the adjusted model.