The "Bundle Busters": Incidence and Costs of Postacute Complications Following Total Joint Arthroplasty.

Background: Recently, a bundled payment model was implemented in the United States to improve quality and reduce costs. While hospitals may be rewarded for lowering costs, they may be financially exposed by high cost complications, the so-called bundle busters. We aimed at determining the incidence, etiology, and costs of postacute complications after total joint arthroplasty (TJA).

Methods: A retrospective study was conducted using a prospectively collected database of patients who underwent primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) from January 2015 to April 2016. Nurse navigators performed postoperative surveillance to identify patients with complications and unplanned clinical events in the 90-day postoperative period. This was combined with episode-of-care costs provided by third-party payers to derive the mean and per capita costs of postacute complications and clinical events.

Results: Among 3018 THA and 5389 TKA patients, 3.35% of THA and 2.62% of TKA patients sought emergency department or urgent care services, 2.62% of THA and 3.69% of TKA patients required hospital readmission, and 3.99% of TKA patients required manipulation. Joint-related complications were more common following THA, whereas medical complications were more frequent after TKA. The most costly complications after THA were periprosthetic fracture, dislocation, and myocardial infarction, compared to deep infection, myocardial infarction, and pulmonary embolism after TKA.

Conclusion: Joint-related complications were among the most costly events after TJA, and given their higher incidence after THA, had a larger impact on per capita costs. Medical complications were more common after TKA and more costly. Despite these events, postacute complications made up less than 5% of the total 90-day costs of TJA.