Early Readmission and Revision After Total Joint Arthroplasty: An Analysis of Cause and Cost

Background: Bundled payments for total joint arthroplasty (TJA) were instituted by the Centers for Medicare and Medicaid Services (CMS) to reimburse providers a lump sum for operative and 90-day postoperative costs. Gaining a better understanding of which TJA patients are at risk for early return to the operating room (OR) is critical in preoperative optimization of those with modifiable risks, which could improve bundled-payment performance. Purpose: We sought to identify the most common reason for readmissions, as well as patient characteristics and costs, associated with early return to the OR among TJA patients. Methods: This was a retrospective cohort study of Medicare patients who had undergone primary total hip or knee arthroplasty (THA or TKA) between 2013 and 2018 at a tertiary care hospital. We used the CMS research identifiable files database to identify the most common reasons for readmissions and revisions within 90 days of surgery. Total billing claims were used to determine the cost of early readmissions and revisions. Multivariate regression analysis was used to determine the characteristics associated with early readmission or revision. Results: Out of 20 166 primary TJA patients identified, we found 1349 readmissions (5.6%) and 163 (0.8%) revisions within 90 days of surgery. Dislocation was the most common indication for readmission, and periprosthetic joint infection was the most common indication for revision. Early return to the OR was associated with a mean $105,988 (standard deviation [SD] = $76,865) in CMS claims for the inpatient stay. Factors associated with a higher risk of early reoperation were female sex, THA, longer length of stay, and discharge to long-term care facility. Conclusions: This retrospective cohort study found that early return to the OR after TJA increased overall 90-day costs by 260%, suggesting that early reoperation might have a significant impact on bundled payments. Further study is warranted.