Outliers of Total Shoulder Arthroplasty in the Bundled Payment Era

Background: The Centers for Medicare & Medicaid Services (CMS) implemented the Bundled Payments for Care Improvement Advanced (BPCIA) Model that covers 90-day care episodes after select orthopedic procedures including anatomic or reverse ball-and-socket total shoulder arthroplasty (TSA/rTSA). This study investigated whether patients undergoing TSA/rTSA for non-degenerative processes incur higher costs than patients undergoing arthroplasty for degenerative processes.

Methods: A retrospective review was conducted of all patients at a single academic medical center enrolled in the BPCIA model for TSA/rTSA from October 1, 2018, through December 31, 2022. We investigated whether patients undergoing arthroplasty for non-degenerative indications accrued more 90-day postoperative costs compared to patients undergoing arthroplasty for degenerative processes. A Break Even Ratio (BER) was calculated to determine the number of degenerative TSA/rTSA that would need to be performed to account for the increased expenditures associated with non-degenerative TSA/rTSA.

Results: One hundred patients met inclusion criteria during the study period. Costs for TSA/rTSA due to non-degenerative indications exceeded bundle payment amounts at a significantly higher rate compared to degenerative indications (43% versus 18%, p = 0.021). TSA/rTSA for non-degenerative indications was also associated with significantly higher total costs ($27,100 versus $22,200, p = 0.014), significantly more postoperative Emergency Department visits (43% versus 18%, p = 0.035), and longer hospital length of stay (2.2 versus 1.6 days, p = 0.121). BER analysis demonstrated 1.22 to 1.54 TSA/rTSA for degenerative indications need to be performed to equal the total spending of one TSA/rTSA for non-degenerative indications.

Conclusions: Patients undergoing shoulder arthroplasty for non-degenerative indications within the CMS BPCIA bundled payments program were at greater risk for incurring higher costs than allocated target payments, as well as significantly higher costs when compared to patients undergoing arthroplasty for degenerative processes. We may need to consider the roles bundled-payment programs have for these patients.