Ambulatory shoulder arthroplasty provides a mild reduction in overall cost compared with inpatient shoulder arthroplasty cost of ambulatory shoulder arthroplasty.

HYPOTHESIS

The purpose of this study was to determine the relative cost difference of inpatient vs. ambulatory total shoulder arthroplasty (TSA) procedures.

METHODS

A retrospective case series was performed to identify a consecutive series of patients who underwent primary anatomic or reverse TSA at 2 orthopedic specialty hospitals between September 2015 and August 2020. Those undergoing surgery for fracture or revision were excluded. Itemized facility costs were analyzed with a time-driven activity-based costing model and compared between ambulatory and non-ambulatory procedures. Ambulatory patients were defined as those admitted and discharged on the same calendar day. All other patients were considered non-ambulatory.

RESULTS

A total of 1027 patients were analyzed, comprising 38 ambulatory patients (3.7%) and 989 non-ambulatory patients (96.3%). There was a higher proportion of anatomic TSA than reverse shoulder arthroplasty in the ambulatory group (81.6% vs. 51.7%, P < .0001). Overall, there was no difference in cost between the 2 groups ($8832 vs. $8841, P = .97). However, personnel costs were greater in the non-same-day group ($1895 vs. $2743, P < .0001) whereas supply costs were less ($6937 vs. $6097, P < .0003). When implant costs were excluded, outpatient shoulder arthroplasty provided a cost savings of $745.

CONCLUSION

Ambulatory shoulder arthroplasty provides a mild cost savings of $745 after controlling for fixed costs. This is much less dramatic than previously reported and should raise concern as shoulder arthroplasty continues to be targeted by payers as a potential for cost savings through decreased reimbursement.