Thromboprophylaxis in patients admitted to inpatient rehabilitation and skilled nursing facilities post total joint arthroplasty.

Objective: Thromboprophylaxis has significantly reduced the incidence of venous thromboembolic events (VTE) after total joint arthroplasty (TJA). Recent studies have established protocols for VTE prevention using aspirin, given its comparable efficacy to prophylactic anticoagulants and a lower risk of bleeding complications. However, patients admitted to inpatient rehabilitation (IPR) or skilled nursing facilities (SNF) after TJA may require more potent agents due to an increased risk of VTE. This study aims to compare the incidence of symptomatic VTE and postoperative complications in TJA patients receiving aspirin versus anticoagulants in the setting of IPR and SNF.

Methods: We reviewed an all-payer, national database for patients who had hip and/or knee osteoarthritis who underwent primary TJA between October 1, 2015 and April 30, 2021 (n = 713,548). Patients discharged to IPR or SNF were identified using CPT codes. A propensity score match was performed to limit potential confounders. Patients were stratified into aspirin (n = 2,343) and anticoagulant (n = 2,343) cohorts based on the postoperative VTE prophylaxis they received; anticoagulants included dabigatran, enoxaparin, heparin, rivaroxaban, and warfarin. Complications were identified using ICD-10 codes and included VTE, aseptic revision, cardiac complications, periprosthetic joint infections, surgical site infections, the need for transfusion, and wound complications 90 days after surgery.

Results: The aspirin cohort had a VTE incidence of 4.4% compared to 2.3% in the anticoagulant cohort (p <.001), indicating nearly double the odds of VTE with aspirin use compared to anticoagulant. The odds ratio for VTE was 0.52 (95% CI: 0.37-0.72), with the aspirin cohort as the reference. Incidence rates of other complications were similar between the two cohorts.

Conclusions: This study demonstrates a higher risk of VTE with aspirin compared to anticoagulant in patients discharged to IPR or SNF after primary TJA. Surgeons should consider using rivaroxaban, enoxaparin, heparin, dabigatran, or warfarin for VTE prophylaxis instead of aspirin in these high-risk patients.