Risk of venous thromboembolism after shoulder arthroplasty in the Medicare population.

BACKGROUND Chemoprophylaxis for venous thromboembolism (VTE) is considered standard of care after lower but not after upper extremity arthroplasty. Medicare claims data were analyzed to determine the national incidence of symptomatic VTE after shoulder arthroplasty during the index surgical admission and after discharge. METHODS Incidence of VTE was compared between shoulder arthroplasty and lower extremity arthroplasty, and patient-specific risk factors for pulmonary embolism were determined for shoulder arthroplasty. Finally, the incidence of surgical site bleeding was determined for each type of procedure. RESULTS VTE complications occurred in 1.2% of lower extremity and 0.53% of shoulder arthroplasties. Patient factors that were associated with an increased risk of VTE included a principal diagnosis of fracture, history of VTE, cardiac arrhythmia, presence of a metastatic tumor, coagulopathy, congestive heart failure, alcohol abuse, and obesity. Adjusted rates of VTE were generally higher for lower extremity compared with shoulder arthroplasties. Prevalence of readmission for VTE was higher for shoulder hemiarthroplasty than for total shoulder arthroplasty. Wound hematoma rates were similar between shoulder and lower extremity procedures. CONCLUSIONS VTE rates after shoulder arthroplasty were generally lower than those after lower extremity arthroplasty. We believe that the risk of bleeding combined with the lower rates of VTE with existing lower rates of chemoprophylaxis does not warrant the routine use of anticoagulation. Use of mechanical prophylaxis combined with aspirin may be sufficient for shoulder arthroplasty patients who are not at increased risk of VTE. Chemoprophylaxis with agents other than aspirin may be warranted in patients with a demonstrated risk of VTE.